


Something You Can't Measure

by Pomander



Category: Undertale (Video Game)
Genre: 10 Reasons Not to Date Your Boss, Age Difference, Awkward Flirting, Grieving, Happy Ending, Hopefully weird in a funny way, Insecurity, Jealousy, M/M, Minor Character Death, Mourning, NO WINGDINGS, Power Imbalance, Romance, Science I Just Made Up, Skippable Smut, Slow Build, Very Minor, Weird smut, alcohol mention, not dadster, pre-game
Language: English
Status: Completed
Published: 2016-01-07
Updated: 2016-10-26
Packaged: 2018-05-12 09:40:20
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 50
Words: 99,838
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5661667
Author URL: https://archiveofourown.org/users/Pomander/pseuds/Pomander
Summary: <blockquote class="userstuff">
              <p>While his old crew finishes their work on the Core, Doctor W.D. Gaster turns his attention to new areas of research. Joining him are four new scientists who don't quite know what they're in for, and a king who seems happy to overlook some of the risks to these new experiments.<br/>Sans has always admired the famous Dr. Gaster, and always dreamed of working with him. But how much can you admire someone you don't really know? And what are you supposed to do when that admiration turns to something else?</p>
            </blockquote>





	1. Welcome to this happy place... welcome.

If he hadn't been standing where he was, Sans might not have believed that hard work ever _really_ payed off. But after sweating his metaphorical butt off, pulling all-nighters, and taking ridiculous tests, he had graduated college early and was now standing (along with two new colleagues) in front of living legend and royal scientist Dr. W.D. Gaster.

  
The very same Dr. W.D. Gaster, Sans would add, (if he was ever asked) who designed the Core that was now powering most of the Underground. The one who had written numerous books on theoretical physics and magical theory. The monster who, in Sans's own personal opinion, would finally be responsible for bringing down the barrier that kept them all underground. It was only a matter of time, and Sans wanted to be there when it happened. He had hoped to be farther along in his schooling before joining Gaster's team, but when he heard there were research positions open at the lab, he couldn't resist applying, just to see if they'd hire him.

  
And he had gotten lucky, or else actually impressed _the_ Royal Scientist and his team, because here he stood in a new lab coat, in front of the monster who had inspired him into the field of science in the first place. Gaster was now fidgeting with the sleeve of his labcoat as he looked over the three new monsters who would be working under him. Behind him was a short, feathered scientist who Sans had never seen before.

  
"It is my pleasure to finally welcome some fresh faces to the Laboratory!" Dr. Gaster exclaimed, with a flourish of his hands. "I'm so excited to have the three of you joining our team. My assistant, Doctor Larkeet-"He motioned to the monster behind him "-will be showing you around the lab while I finish getting things shuffled around, but first, why don't you three introduce yourselves to the team? Professor Wickett?"

  
The elderly waxen monster next to Sans stepped forward and spoke, introducing himself as a former teacher at Hotland University, who was happy to be working again after taking much-needed hiatus for his health.

  
Sans was next. "I'm Sans Calibri, I just graduated this past year with my bachelors in physics, annnd I'm very happy that positions here opened when they did, or I'd have had a real hard time finding a job in my field." He chuckled nervously. "It's always been my dream to work here." He looked over at Gaster, who smiled politely back at him.

  
Last to introduce herself was Juneborg, a recent engineering graduate who was just _so_ excited to be working with such esteemed professionals. "I had actually assumed I'd be doing maintenance on the Core when I graduated." She admitted, sheepishly. "So being here is a pleasant surprise. I can't wait to put my skills to use!"

  
"Excellent, excellent!" Said Gaster. "So you all know, we'll have one more joining us later this week. An intern, Alphys, who's still working on her Doctorate. She'll be helping me upgrade some of the computers we use here in the lab, as well as a few other things..." He paused, drumming his fingers together. "Dr. Larkeet? Please take over while i get their key cards ready. I'll show them the Lab Proper when you're done up here." Larkeet nodded as he shuffled away.

  
"I'm Doctor Larkeet, obviously!" She announced. "I've been working at this laboratory for twelve years, and I've been Gaster's assistant for six of those. Not consecutively, mind you!" Her feathers ruffled as she spoke. "Things might be a bit chaotic around here for a few weeks while we all get settled. Now that construction of the Core is pretty much complete, our team is splitting so we can begin a new chapter in our research while finishing and maintaining the Core itself. That is why the three of you are here, to assist in our research on the barrier, and some... other things, which Gaster will explain when he shows you the Lab Proper. Now! If you'll follow me, I'll show you around the laboratory office!" She flapped excitedly and turned on her heel, leading them upstairs.

  
From what Sans gathered, the upstairs office and the lobby of the Laboratory were mostly for show and for storage. There were several desks and computers, a collection of overstuffed filing cabinets, a small kitchen area with a fridge and a coffee pot, and a few pieces of equipment, mostly printers and recording devices. Larkeet showed each of them their assigned desk, asked them to be _very_  careful with food and beverage around their work, and explained the importance of maintaining the office as a safe and clean environment for everyone.

  
"When the general public is shown into the lab," she explained, "this is what they see. Any sensitive or dangerous equipment is kept in the basement, the Lab Proper. This is to protect civilians, protect our equipment, and because some of what we do here needs to be kept secret. I'm sure Doctor Gaster will explain all that to you shortly." She led them back down stairs and over to an elevator door where Gaster was waiting for them, three lanyards dangling from his hands.

  
"I have a key-card for each of you, with your name printed on it." He said, handing them to each of the new members. "It is of extreme importance that you **don't** -" he placed a hand on Sans' shoulder "-misplace your key-card." His tone was serious, but he was still smiling as he looked at the three of them. Heat rose to Sans' face. Was he being singled out? He hadn't done anything wrong, not yet. But Gaster removed his hand and continued to speak, his attention on the group like he hadn't even noticed what he had done. "This elevator doesn't move until every passenger has scanned a key-card, so you won't be able to get to the Lab Proper without one. You might find that makes it very difficult to do your job, so please do keep track of them!"

  
He chuckled to himself and turned away from them as he retrieved a key-card of his own from the pocket of his lab coat. He swiped it against a panel by the door frame, and the elevator doors opened. "If each of you will swipe your card and join me in the elevator, I will show you around the basement, and finally explain some of what you'll be doing here, and why we're a bit secretive about what we do."

**Notes for the Chapter:**

> Sorry for the slow first chapter, had to get some introductions out of the way since some new monsters will be joining us!


	2. The Lab Proper

**Summary for the Chapter:**

> Come into the lab, and see what's on the... I mean... what you'll be working on while you're here.

Gaster was silent through the long elevator ride to the basement. Sans was grateful for this, as the doctor tended to talk with his hands when he spoke, an old habit he was well known for. Being crowded in near Gaster's elbow, Sans was almost _guaranteed_ to get thwapped in the face if a conversation were to strike up.

  
He glanced over at his new colleagues and saw that Juneborg was just as nervous as him. Her eyes darted around the elevator and her mandibles clicked in an uneven rhythm. Sans wondered if it was the enclosed space that was getting to her, or if like him, she didn't enjoy being kept in the dark about the work she'd be doing here.

  
Professor Wickett seemed unfazed by any of this. His eyes were closed and he was smiling serenely and swaying from side to side, probably enjoying the elevator ride down. _Maybe he's worked here before,_  Sans thought.

  
But when the elevator finally came to a stop, all three of them were caught off guard, reaching quickly for the railing to regain their balance from the sudden jolt. The doors opened and Gaster walked swiftly out of the elevator, turning back to the others while they followed him into the short corridor ahead.

  
"I must ask that while you are down here, you take your work very seriously." He said. "The... equipment we are working with here in the Lab Proper is either very sensitive or very dangerous. If you are distracted, if you are tired, if you are inhibited or inebriated, you will not be able to perform your job safely, and it could cost you your life or the lives of everyone in this lab. I have already lost one member of my crew while constructing the Core, I don't want anything like that to happen here." The air around them was heavy, solemn. "Part of why we're only starting this research now is because we rely on a very large amount of energy, both electric and magical, drawn in from the Core. If handled improperly it can be fatal. Please keep that in mind." With this he turned away, and lead them forward.

  
A number of screens lined the walls of the corridor they were in. Gaster explained that these were meant for displaying performance data for the machines in the lab, but could also be used as a sort of memo system, a means of reminding yourself and your coworkers (if need be) what you are working on, or if they need to take any extra precaution when nearing your area. "It's a good idea to glance at the screens on your way into the lab," said Gaster, lightly. "See what's going on before you get into your day's work. I'll show you how to put a message up on screen before we leave today."

  
Sans glanced at the screen next to him. On it was a message about how a broken oscilloscope in the lab had been repaired and tested, and was now ready for use. At the bottom of the message was a smiling emoticon that looked suspiciously like Gaster's face, and a little hand symbol giving an "OK" sign. Sans snorted, but managed to suppress his laughter. Despite his serious tone, Dr. Gaster apparently had a sense of humor.

  
They moved on into a series of rooms and hallways filled with computers and machines in various stages of age and wear, including a single vending machine. ("It was installed by the previous royal scientist." Gaster Explained. "We keep it down here mostly at King Asgore's insistence. You may use it, but keep any food or beverages in this room, and make sure your hands and clothes are clean before resuming your work.") 

  
They walked past a large oscilloscope that looked to be in great condition. _If this was the one that had been repaired_ , Sans thought, _they did a fantastic job_. There was a single water closet tucked in at the back of one hallway, with a chemical shower behind a shower curtain. Sans figured there was no point in this kind of safety equipment if you couldn't easily access it in an emergency, but kept quiet. Just past this water closet was a large sign on the wall that read 'AUTHORIZED PERSONNEL ONLY. PROCEED WITH EXTREME CAUTION.'

  
Everyone but Gaster stopped walking. The machine in the room ahead of them was large, hollow, and looked to be unfinished. But its spiked form was unsettling, even to Sans. It looked like the malformed skull of a very large animal, but the top half was hinged at an unnatural angle, and the jaw was split lengthwise. Sans wished he hadn't noticed its eyes, one of which was aimed directly down the hallway at them. The whole room radiated with a strange and unpleasant energy that made Sans's pulse race.

  
Gaster stood next to the machine with a proud look on his face and gave it a hearty thwap, which reverberated through the shell and made his hesitant audience jump back and gasp.

  
"Ah! No, it's- You see it's not even... it's not plugged in or anything right now, it's completely inert!" He said. "Please come closer, this is the whole reason why we're here."

  
Professor Wickett slowly approached, looking the machine up and down. "Is it some sort of weapon?" He asked. "Why?"

  
"It's a blast cannon!" Gaster replied happily. "And once complete, I believe it will be powerful enough to destroy the Barrier!"

**Notes for the Chapter:**

> (8 D)  
> 


	3. Let's split up, gang!

"Why does it look so menacing?" Juneborg whispered. She kept her distance from the cannon and her arms pulled close to her body. There was no mistaking her fear of the thing.

  
"Well, it's meant to look a bit intimidating, I admit." Said Gaster, twirling one hand in the air. "If we break free to the surface, there's no knowing for sure how humans would react, but based on their past actions, I'm willing to bet they won't be happy. I don't think our population can handle losing another war, so I'd like to try and ensure we have the upper hand."

This did nothing to assuage Juneborg's tension.

  
"How is it supposed to break the barrier?" Asked Sans "How does it work?"  
Gaster's face brightened.

   
"Well, while my crew and I were studying the Barrier, we realized that it has a distinct sound to it. It's a very low frequency, almost a rumble. If any of you have been up to the barrier, you've probably heard it. The goal of the cannon is to fire an immense blast of magical energy that resonates at the exact same frequency."

  
"Like shattering a wine glass with a high note?"

  
Gaster clapped his hands together. "Exactly like that!" He exclaimed. "But to be sure, the beam will also be exerting a huge amount of force. We will weaken, then shatter the barrier. But this will require a tremendous amount of energy. Thus, we needed the core to be fully operational before implementing this plan. We also need to continue to run tests on the barrier, to make sure the resonant frequency stays constant. And, if possible, I'd also like to run tests on one or more of the human souls, to find out whether they have their own resonant frequency, and whether it interferes with that of the Barrier."

  
"How are you going to test it?" The thing was huge, and Sans had a feeling it probably wasn't easy to move around. As is, it definitely couldn't fit in the elevator.

  
Gaster motioned to the wall on the opposite side of the room, and everyone turned their attention to what looked like a thick black tarp covering most of the wall, from ceiling to floor. Or, at least it was shaped like a tarp. Sans shifted his head from side to side, but couldn't see any folds in the fabric. There was a tiny white circle in the center of the tarp, however, squinting, Sans saw it was a bullseye.

  
"That material is capable of absorbing whatever amounts of energy we can throw at it, and then some." Gaster said. "I designed and enchanted it myself, and I've already tested two smaller prototype cannons with it. It also works as a hand towel in a pinch." He winked at the group.

  
Sans laughed. Juneborg let out a small, polite chuckle. The tension she had been holding in was visibly draining, little by little. Wickett sighed and shook his head.

  
"Well," said Gaster. "I think that wraps up our tour of the Lab for now. I'll show you how to send a memo to the display screens in the hall, and then I have work for you upstairs. Juneborg, Professor Wickett, I have copies of the design plans for the internal and external structure of the Cannon, which I need you both to familiarize yourselves with, as you'll be working with me on it, down here." Juneborg's eyes were wide with panic, apparently it hadn't registered to her until that moment that she, as a mechanical engineer, would be working on the terrifying blast cannon. "Calibri," he added, turning to the skeleton, "You will be assisting Doctor Larkeet with her tests on the barrier. I'll send the other two up the elevator first, there's an Oscilloscope down here that you'll be needing, but it's a bit heavy. So if you could help me wheel it over to the elevator, I'd be very appreciative."

  
Sans nodded, trying not to let his disappointment show. So he wouldn't really be working _with_ Gaster, what a shame. Maybe if he had been more qualified, or had done a better job on his interview... No, working in the Hotland Laboratory was still a huge honor. He would still work hard, even if he was just running field tests. He looked slowly around the room, taking it in. He noticed that there were two closed doors on separate walls that Gaster hadn't mentioned. What were they?

  
"Doctor Gaster, sir? Are those both storage closets or something?" He asked, gesturing to the doors with both hands.

  
"One of them is, yes. The other opens to a room where I keep one of my personal projects."

  
"Personal projects?"

  
"What little free time I have is sadly still spent here, hard at work."

* * *

  
As promised, Gaster demonstrated for them how to send a message to one of the display screens, then sent Juneborg and Professor Wickett back up on the elevator, while he and Sans maneuvered the heavy oscilloscope down the halls.  
"So," Sans ventured as they approached the elevator, "assistant to the assistant, huh?"

  
Gaster tapped the button to bring the elevator back down, he wasn't looking at Sans. "Are you unhappy with your assignment?" he asked.

  
"No, not at all! I was just-"

  
"Because it may not be permanent."

  
Sans was silent as the elevator doors opened. Gaster turned to look him straight in the eye.

  
"I will probably be needing your assistance on the cannon at some point as well, so you're free to look over the design plans, you'll have access to them. But we'll have to see how things go. I wasn't expecting that kind of reaction from Wickett, he really didn't seem to approve of the Cannon. He's mentioned to me before that he's holding out hope for Asgore to break the barrier, but there's no telling how long that could take, he's still two souls short. We could be down here for another century before the next human wanders down, why not take action??"

  
"Well..."

  
"My apologies, I'm getting off topic. Let's push this into the elevator already. Where I'm going with this is that if he becomes uncooperative, or tries to back out of his assignment, I will ask you to take his place. I just don't want to give him the option of backing out right now because I need his expertise. The same applies to Juneborg, I would rather she overcomes her instinctual fear of the cannon, rather than backing out now. I have enough people maintaining the core, I need her here."

  
Once they were in, the doors closed and the elevator began its long ride back to the upper lab.

  
"Have you worked with him before? Wickett, I mean." Sans wasn't ready to let go of the conversation just yet.

  
"Oh yes, years ago. He's a monster driven by his morals. Which I find as respectable as I do troublesome. We have our differences, but he's an expert in the applications and limits of monster magic. And he's one of the few monsters who knows anything about human magic. He's invaluable to our team."

  
"Gotcha."

  
"And I believe you will be, too."

  
"Wait, what?"

  
"When I talked with your references, your teachers? They all spoke very highly of you. It's not often a monster of your age approaches this field with such passion and dedication. Not to mention the brains to back them up. I'm aware that your current assignment isn't exactly a chance to show off your skills and knowledge, but if you can prove your diligence, I'm sure there's a place for you here."

  
"Thank you, sir." was all sans could manage in reply. The compliment caught him off guard, but it was nice to have his hard work recognized. (It almost made up for all the sleep that hard work had cost him) At least now he had an idea of how to impress Doctor Gaster. He would work hard, stay determined, and prove he was a good fit for this lab.

* * *

  
Rather than taking him directly to the barrier, Doctor Larkeet trained Sans on how to use the oscilloscope. She insisted he become familiar with the machine before they headed out to do any real testing. 

"By the time you're done with that, and we get out there with this thing, the day will be pretty much over." she said. "So what we'll do is take it to a storage room right near the throne room. We can leave it there over night and use it tomorrow morning. We just need to cover it first, wo it doesn't get any dirt or pollen in it. Those flowers in the royal garden are so messy."

  
Near the end of the day sans helped her load it onto a motorized cart that made moving it around so much easier. They brought it to the castle and made small talk along the way. Sans learned that Doctor Larkeet was also an amateur hockey player, and had two children, one of which was going to be in high school soon. He mentioned his own brother who was going to be graduating. A royal guard showed them to the storage room they could keep their equipment in.

  
Once they were finished locking up, Larkeet told Sans she'd see him tomorrow. "I'm going straight home, since I live closer to the castle than the lab." she said. "You should go back and check in with Doctor Gaster, before you go home, but tomorrow morning just meet me right outside the castle. Have a good night!"

  
Sans walked slowly back to the lab, and when he arrived he saw Wickett and Juneborg already on their way out. They said goodbye for the day, and told him Gaster was up in the office area.

  
Sans headed in and up to the office, where he saw Doctor Gaster seated at one of the larger desks, still and silent, his eyes closed. Was he sleeping? Sans decided to be polite and knocked gently on the desk next to him, to announce his presence. Gaster startled and turned to Sans, rubbing his eyes.

  
"Ah, Mr. Calibri, was there something you needed?" Gaster asked, flushing. He really had been caught napping.

  
"No, sir." said Sans. "I was just heading home for the day, if that's alright with you. And I'll be meeting Doctor Larkeet at the castle first thing tomorrow morning.

  
"Hm, alright." Gaster rose from his chair. "That sounds fine."

  
"You heading home, too?"

  
"No, I'm going down to the Lab Proper, I still have some work to do. Have a good night, Mr. Calibri. Get home safe." He headed to the stairs, Sans followed.

  
"Good night, sir, get some rest." Sans winked.

  
Gaster waved lazily and stepped into the elevator. Sans left the lab and then took a shortcut back to his apartment. His brother, Papyrus, was waiting for him.


	4. Well, good luck with all that!

"Hello, Sans! How was it? Your first day, did it go well?" Papyrus was sitting just outside Sans's apartment, holding a paper bag in his lap, and kicking his legs excitedly as Sans approached.

  
"It was good, Papyrus. wanna come in?"

  
"Yes please!"

  
Sans dug out his keys and unlocked the door. Papyrus followed him in.

  
"Oh!" said Papyrus "I haven't seen this place since you got unpacked! It's..." his voice trailed off as he surveyed the tiny, dark, cluttered apartment.

  
"still small and not actually efficient?" Sans offered.

  
"...yes." Papyrus decided after a moment.

  
"Yeah, well so am I. That makes it a perfect fit."

  
"I suppose it's too late for you to move back? it would be really nice having you back home, even if that means sharing a room." He walked over and sat on the only chair in the apartment, placing the paper bag on the floor beside him. Sans sat on the edge of the bed.

  
"C'mon, it's been a week. Give yourself some time to adjust. Isn't it nice not having me around, with the lamp on at all hours of the night, leaving my books everywhere?"

  
"I just feel so..."

  
"Bonely?"

  
"Sans! I burned that joke book ages ago. When are you going to let it die?"

  
"When the jokes stop being so Humerus?"

  
"I was trying to open up to you and you _ruined_ it!"

  
"Heh. Sorry. Go on?"

  
"No, the moment's over. Tell me about your day at work or I'm leaving." He crossed his arms in a mock show of indignation.

  
Sans stretched one of his hands while he thought over his day. "It went pretty well," he decided. "Found out I'm gonna be 'Observing the Barrier.' Or at least the machine I use will be. I'll be writing down and keeping track of the results."

  
"Writing things down? How scientific."

  
"Well a lot of science is just-"

  
"It's boring, I get it. What's Mr. Gaster like, now that you finally get to work with him?"

  
"It's Dr. Gaster, Paps. And he's..." Sans thought over what he had seen of Gaster during that day. "... more expressive and lively in person than in his writing. Maybe also a bit less professional. He used emoticons in a memo, and I saw him asleep at his desk, just sitting straight up. It was kinda cute." He hadn't registered the word until just after it left his mouth.

  
"What?"

  
"I mean it was unexpected."

  
Papyrus grinned. "That's not even close to what you said, Sans."

  
Sans's face was all blush at this point, he could feel it. "Anyway! He's great, my coworkers are cool, and I'm going to be doing Rad Science Things forever. End of story. How's chess club going? You talk to anyone yet?"

  
Papyrus's smirk dropped. "Well, no." he said. He reached up to scratch the back of his neck. "I mean Chess is supposed to be a quiet sport, a game of wits, I would hate to ruin anyone's concentration."

  
"Fair enough, I guess. What about your art club?"

  
"Not yet, we're all busy with our projects for this year's show."

  
"Aerobics?"

  
"Not much room for talking when you're feeling the burn."

  
"Paps, I just don't understand how you can participate in like, nine different clubs and not strike up a conversation with anyone. First step of making friends is just talkin' to them."

  
"I'm shy." Papyrus fidgeted with his hand bones, twiddling his fingers.

  
"I can tell." Sans gave his brother a gentle look.

  
"Sorry."

  
"Hey, you're fine. People will realize how cool you are someday; You've got time. So, uh, What's in the bag?"  
Papyrus reached down to grab the bag and handed it to Sans. "Biscuits, Mom made them for you."

  
"Cool, I was running low on chalk."

  
"I'll tell her you said that. But she still wants you over for dinner some time. Just call whenever and come over. Don't ditch us just because you're an adult with a job, okay?"

  
"Yeah, I'll try." Sans stood up and stretched. "It's getting late though, I gotta get to bed. don't you have homework?"

  
Papyrus nodded and stood up as well. They hugged tightly, and he wished Sans luck as he left.

  
Sans fixed up bowl of soup, and dunked a few biscuits in. They weren't terrible, just chalky and flavorless. Sans chalked it up to the 'added calcium' his mother liked to put into her baking. After dinner, he relaxed and fell asleep.

* * *

  
He was up early the next morning, and out the door with time to spare. He arrived at the castle doors a few minutes before Dr. Larkeet, who was pleasantly surprised to find him waiting.

  
"Showing up early doesn't net you any brownie points," she said, "but it's a great habit to get into. C'mon, let's get started."  
He followed her into the castle, back to the storage room where they had put their equipment the day before.

"It's gonna be a pain to drag this out every morning." Larkeet sighed, "I guess the new intern's got ideas for operating our equipment remotely, but until she can actually do something about it, I hope you like traipsing from here to the lab all the time."

  
Sans shrugged. "I'll get used to it. Are we both coming out here every day?"

  
They began hooking up the machines. Sans got the recording equipment ready, while Larkeet configured the scope.

  
"Only for the first week." She said. "Then you'll be running this one by yourself. There isn't a lot to manage; the job is mostly making sure the machine runs consistently, and watching for interference. At the end of the day you gather your data, put things away, and go back to the lab to feed that days data into the system, so we can keep track of it."

  
"That sounds pretty boring."

  
"It'll go by faster if you have something to read. Stop by the lab first in the mornings, after today. Dr. Gaster will probably have extra work for you to go through while you're here. Now, do you see these settings, on the scope? This is what you'll have it set to every morning, so write those down."

  
The next six hours dragged on horrendously. Sans took notes while Larkeet instructed him on things to keep an eye out for while the machines were running, like signs of interference, and what to do if the recording equipment wasn't syncing properly.

  
At the end of the day, she accompanied him back to to the lab and helped him record their data into the computer. They were the only two in the upper part of the building; Sans realized he hadn't seen Gaster at all that day, and felt a little disappointed. On his way home, he realized he probably wouldn't see much of anyone in the lab, if he was always out at the barrier. _How exciting_.

* * *

Doctor Gaster shuffled about restlessly, tapping a pen on every surface within his reach. He was tucked away in his pesonal office at the back of the lower lab, flipping through paperwork without really reading anything. His mind scrambled with thoughts of the future.

  
Everything was beginning to come together, after over a decade's work. It felt good. He was nervous, but even if the cannon failed to destroy the barrier, they still had the Core. The whole Underground now had a reliable source of power, and that was a legacy he could be proud of. Asgore would be devastated though; he had put a lot of his faith in this plan.

  
_That_ , Gaster figured, _is at least better than counting on this_. He sighed, his eyes scanning over all the unfinished work scattered around him. He was nowhere near success with his personal project, It was still basically a fantasy. But now that things were moving forward, he would have more time to figure out... _time_.


	5. Hey, no sweat!

The next morning, Sans rubbed the sleep from his eye sockets and left early for work. With any luck, Dr. Gaster would have something for him to do while monitoring the Barrier. When the lab doors opened and he stepped in, he found a startled Gaster in the middle of the lobby, turning to face him.

  
"Ah, good morni-" He cut his greeting short; the doctor was making very urgent shushing motions at him and beckoning him forward. He approached silently, unsure of exactly why he needed to be quiet.

  
"Was there something you needed, Sans?" Gaster whispered.

  
"Um Dr. Larkeet said you might have something for me to work on while I'm out today? So I thought I'd drop by and check."

  
"Oh, well, I don't have anything... ready for you yet? But I think we're out of coffee, and I'd love it if you could go out and get some. It's still early, isn't it?"

  
"Yyyeah. Have you been here all night? You look pretty tired." In actuality there was something a little off-kilter about the doctor, but Sans couldn't pinpoint what it was.

  
Gaster chuckled softly. "I'm here most of the time, Sans. You should adjust yourself to the sight of me being tired. But I think some coffee would really help me wake up."

  
"Okay, sure. What kind do you like?"

  
"Just get whatever..." Sans watched a smile creep across the doctor's face. "Whatever you think has the highest caffeine content."

Okay, something was definitely weird here. There was no reason for Gaster to look so smug.

  
Sans gave him a thumbs up and backed out of the lab slowly, looking around himself cautiously. Nothing else in the lab seemed different. The doors closed behind him and he decided to put the weirdness out of his mind and just roll with it. Maybe that was just how Gaster acted in the morning, when he was tired.

  
At the market, he looked over the meager selection of coffee. Light roast, dark roast, decaf. Sans had to admit he didn't know much about coffee, he only drank the stuff when he needed to stay awake. He grabbed a bag of the dark. He figured Gaster would want something strong, and the dark roast was probably the one with more caffeine. Maybe that had been a joke, the caffeine content was the same as long as it wasn't decaf, right?

  
When he got back to the lab, Dr. Gaster was no longer in the lobby. Sans began brewing a pot of coffee, and hoped the noise wouldn't be too much. He looked upstairs, and found Gaster asleep at his desk again, this time slouched over on the desk top.

  
_Wow, he must really be tired_ , Sans thought. He returned to the coffee pot without a word and poured a cup for the docter, and afer a moment of consideration, one for himself. He brought both mugs upstairs, and set set Gaster's on the desk next to him with just enough noise to let the doctor know it was there.

  
Sans took a sip of coffee and watched as Gaster's eyes opened and flicked from the cup next to his head, up to Sans, and back.

  
The doctor sat up slowly, rubbing his face with one hand and reaching for the coffee with the other. "Good morning, Mr. Calibri." He mumbled. "Thank you for the beverage."

  
Sans shrugged. "Any time. I figured the dark roast would have more caffeine, so I grabbed that. Is it okay?"

  
Gaster chuckled and took a sip. "Lighter roasts actually have higher caffeine content, but personally, I like the flavor of dark coffee. Anyway, is there something you needed?"

  
_Well that's irritating_ , Sans thought. _Did he know I'd get it wrong?_ "I just wondered if you had anything you'd like me to work on while I'm out testing, since I'm mostly babysitting the oscilloscope."

  
"Ah, well, I'm not sure I have anything for you to actually DO at the moment. Maybe some papers you could go over and double check for me, though. How much do you like math?"

"That's kind of an unfair question."

  
Gaster chuckled and stood up from the desk, stretching as he walked over to the nearest file cabinet. He opened the top drawer, pulled out three folders, and handed two of them to Sans.

  
"Could you just go through those and make sure they add up correctly?" he asked, setting the third down next to himself. "I was a bit tired when I wrote everything down. I won't need them until the end of the week, so just take your time."

  
"Absoultely." Sans heard the door open downstairs. _Shoot, is it that time already?_ "I should probably head out, Dr. Larkeet's waiting for me. But before I go, may I ask why we needed to be so quiet earlier? No one else was here 'till just now right?"

  
"What?"

  
"When I came in, you were whispering and told me to be quiet? What was that about?"

  
Gaster looked very confused. "I don't recall... perhaps I was talking in my sleep?"

  
Sans shrugged. "You sent me to get coffee in your sleep, then."

  
"That sounds like something I would do, yes."

  
He laughed softly. "Well, please be careful doctor. Sleep walking in a place like this is probably dangerous."

  
Gaster said nothing. Sans got up, waved a hello to Juneborg as their paths crossed on the stairs, and put away his mug before leaving for the barrier.

* * *

  
Doctor Larkeet was waiting for him there. She had brought the equipment out for the day, but this time she stood aside and watched as Sans set things up, making sure he did everything correctly. Once all was set up, she took out a book and Sans began looking through the papers Gaster had given him.

  
By the end of the day, Sans had gotten through most of the first folder. Though the handwriting was sloppy, the mistakes were few. He corrected what he could, and made note of things he wasn't quite sure of, and before he knew it the day was over. Larkeet left early to take care of something at the core, but putting away the equipment was easy enough that he didn't mind doing it alone.

  
On his way out of the castle, he ran into King Asgore.

  
"Good evening, your majesty." He called out as he approached. Asgore waved to him excitedly, grinning wide.

  
"Hello there! You must be one of Dr. Gaster's new recruits." The king said.

  
Sans looked down at his labcoat, and back up. "Heh, what gave it away?"

  
"Haha! Good one! I'm afraid we haven't been introduced. What's your name?"

  
"Sans, Calibri." He said, offering his hand. Asgore shook it eagerly.

  
"Pleasure to meet you, Sans. And how is Gaster doing? I'll bet he's excited for my visit; I sure am!"

  
"Um, I don't see very much of him, so he hasn't mentioned anything. You're visiting the lab?"

  
"Oh yes, I check in every few months to see how things are going. I can't wait to see what he is working on this time!"

  
"He hasn't told you yet?"

  
"Nope! And I want it to be a surprise, so please don't tell me, okay?"

  
"Sure, my lips are sealed."

  
For a moment it looked like Asgore had something to say about Sans's lack of lips, but he let the opportunity pass. "Please tell him I said hi when you see him next? And that I'll be bringing donuts with me instead of cookies, this time."

  
"I'll let him know."

  
"Thank you, Sans, it was a pleasure meeting you!"

  
"You too, your majesty. See you soon!"

  
They waved goodbye and Sans walked down to the lab with a spring in his step.

* * *

  
"Ah, Mr. Calibri! Right On time! I'd like to introduce you to Intern Alphys Rex." Gaster motioned Sans toward the short reptilian monster at his side. "Aphys, this is Sans Calibri, one of the new recruits."

  
She waved nervously at Sans as he reached out to shake her hand. When he pulled his hand back, she reached out to shake. He reached out one more time, but she had already retracted. They stared at each other for a moment, Sans wishing he could take back the awkward first encounter and start over. By the look on Alphys's face, she was wishing the same.

  
"It's a pleasure to, uh, mmmeet you, Mr. Calibri." She squeaked. "And just Alphys is fine."

  
"Same." Sans said, not sure whether he meant it. " And you can call me Sans, too. I don't usually go by my surname, anyway."

  
Gaster's exression shifted slightly. "And how did testing go today, Sans? Is the oscilloscope running well?"

  
"Pretty well, I think. Haven't run into any interference or any sudden shifts in the data yet. Oh, but I did run into Asgore on the way back here; He says hi, he wants you to know he's excited for his upcoming visit, and he'll be bringing donuts."

  
At the mention of Asgore's name, Alphys's face reddened, while Gaster's took on a greenish hue.

  
"Ah, that's coming up soon, isn't it? The 22nd is... two weeks away. I hope we'll actually have something to show him by then." He sighed and rubbed the side of his forehead "I told him to stop bringing treats altogether, but he's relentless, isn't he? It's a business meeting, not a potluck."

  
"S-should I be here, for the visit, Doctor?" Asked a blushing, thumb-twiddling Alphys. "I mean, just in case he has any questions about the new network or something?"

  
"I don't see why not."

  
"Yes! Heheh." She clapped her hands together excitedly.

  
"Also, once the network is ready for use, the oscilloscope Sans is monitoring should probably be the first thing you connect to the Lab. I believe it has been running smoothly enough since you repaired it that we can leave it going for most of the day without worry. And it would be much more efficient to monitor it from here. Wouldn't you say so, Sans?"

  
"Um, yeah, I think so." Sans said, shifting from one foot to the other.

  
"The network will be up and running by this weekend." Said Alphys. "Ssoooo let's plan on Monday for the scope."

  
"That sounds perfect. Sans, why don't you go and enter in your data for the day? I'll be up in a moment, there's something I need to discuss with you."

  
_Oh, fuck._  "Sure, I'll just..." _I'm in for it now_. "I'll be waiting at my desk. Nice meeting you, Alphys."

  
"It was nice to meet you, too." She said. She looked worried for him.

  
He was pretty worried, too.

**Notes for the Chapter:**

> Kind of a lot going on for one chapter, sorry.  
> (Sans, the doctor wants to speak with you ~alone~, shouldn't you be excited?)


	6. It's a sign, at least.

Sans had absolutely no idea what Dr. Gaster wanted to discuss with him, but he was sure it wasn't good. In his mind he shuffled through his every action in the past three days, wondering what he had done wrong, and if it was enough to get him fired. His hands trembled as he typed, hitting extra keys and forgetting to hit the backspace when he had to correct something. By the time he was finished, he could hear Gaster's footsteps on the stairs behind him.

"Ah, good, let me see what you've got there," Dr. Gaster said as he approached. He stood behind the chair, and waited for Sans to scroll to the top of his report, then leaned forward to get a better view of the computer monitor.

Had Sans been nervous just a minute ago? He couldn't recall. Surely, he had never been more nervous in his life than this moment, with Gaster leaning over him, reading his report. The doctor's chest was pressing right into his shoulder, his neck right in front of San's face. Sans could hear him breathing, could smell machine oil and coffee on his unwashed labcoat.

Gaster reached for the mouse, and Sans pulled his hand away from it quickly. The doctor didn't seem to notice, still intently reading the screen. Sans's gaze traced Gaster's form from his fingertips to his shoulder, from his neck to the corner of his jaw, and finally to his face, which held no indication whatsoever that he realized how intimate their position was. Sans suddenly felt smothered, like there wasn't enough air between the two of them. There was a familiar constricting in his chest, something entirely unwelcome squeezing around a heart that he technically didn't even have.

_This can't be happening_ , he thought.

"This is great," Said Gaster, straightening back up. "these results look to be consistent with the ones we were getting before the scope broke. That's a good sign."  
  
Sans took a moment to breathe again before turning around to face him. "Good to hear." he mumbled.

"And were you able to take a look at any of the work I gave you this morning?"

"Yeah- Yes sir. I got through all but ten pages in one folder, I haven't opened the second yet. There wasn't a whole lot that needed correcting, a few missing decimals and such."

Gaster nodded and leaned on the desk next to Sans's, arms folded. "Thank you. When you're finished going through those you can leave them on my desk."

"Was that all you needed to talk to me about?"

The doctor scowled, not at Sans, but at the floor. He began drumming his fingers on the side of his arms, but said nothing.

The panic Sans thought he had pushed down began to rise inside him again. "H-have I done something wrong?" he asked, tightly.

"No." Gaster whispered. "No, I just wanted to ask you what all I said to you this morning, before you came back with coffee. Do you remember?"

"Yeah, I do. You asked me to be quiet, but didn't mention why, you said you didn't have any work ready for me, and you told me I should get some coffee, that it would help you wake up."

"That's all?"

"No, I asked if you'd been here all night, 'cause you looked pretty tired, and you said I should get used to that, because you're here and tired most of the time."

Gaster's expression relaxed a little. "Well, I suppose there's no denying that. Anything else, anything unusual?"

Sans shrugged. "You looked pretty smug when I asked what kind of coffee to get. That was weird. Why?"

"I was just curious what was said. Anyways, there was one more thing I wanted to ask you before you go."

"Yes?"

"I have been calling you by your surname for the past three days and you never said anything about it. Why is that?"

Sans scratched the back of his head. "You're my employer, you can call me whatever you want. I figured it was just a formality."

Gaster's expression soured. "That's not the way it works, Sans. I'll call you whatever you prefer to be called, as long as it's not some ridiculous nickname."

"Thank you, sir."

"Of course. Now, why don't we call it a night? It's getting late, and I still have some things to take care of."

"Sure thing."

On the way home, Sans cursed himself for getting so flustered when Dr. Gaster had leaned over him. The last thing he needed was to be having a crush on his boss. But there it was, the feeling squirming in his chest when he thought back to how the doctor had smelled. He was going to make a fool of himself at some point, he just knew it.

* * *

 

Gaster looked over the security footage for the third time that day, still in disbelief. There he was, whispering with Sans in the lobby. And there he was, asleep at his desk. At least this proved he hadn't been sleepwalking, but that was a small relief.

Whoever had appeared in the lobby moments before Sans's arrival had used his keycard to get into the basement, the elevator records showed that much. Once in the lab proper, they went straight for Gaster's personal office, unlocked the door, and shut it behind them. The footage never showed them leaving, but when Gaster had gone down to check, they weren't there.

He tried to take this as the good sign it should be, that his personal project would be successful despite how impossible it seemed. He picked up the note the intruder left behind and read over it again.

'Don't be afraid to ask for help.' it read. Not a solution, just advice.

_I'll try to keep that in mind._

 

**Notes for the Chapter:**

> I went through three drafts of this chapter, and it came out shorter and shorter each time. I'm so sorry.


	7. We're so professional.

Warm hands reached under Sans's shirt and stroked the front of his spine. He gasped and tried to turn away, but Gaster's body was pressed against him, pinning him firmly to the cool, wet ground. The doctor's lips brushed against his jaw, barely touching the surface of the bone, heating it with small puffs of warm breath. The sensation was electric and ethereal, like gathering static, and Sans writhed under the contact as those lips moved down his neck and across his clavicle.

Cold, black water slowly pooled around their entwined bodies, bubbling up from an unknown source. It had soaked into Sans's clothing, and was lapping against his ribs, making him shudder. He grabbed Gaster by the shoulders and pulled him closer, relishing the doctor's warmth contrasted against the deep, icy puddle they were in.

"You're going to sink." Gaster whispered. This was probably true. if they didn't get up soon, they would be completely submerged.

Sans shrugged turned his head to the side. "Good thing I don't need to breathe."

He woke up tense and covered in sweat.

* * *

 

Gaster drummed his fingers against the shell of the cannon. He hadn’t been home in four days, hadn’t slept properly in four hellish nights. The past week had been far too eventful for his liking, and with Asgore’s visit looming just around the corner the next fortnight was only going to be more of the same. Saturday morning, the stress finally settled on him in the form of a migraine.

He had taken the little slip of paper’s advice, and asked Doctor Larkeet to check on the core in his place. Two capacitors had mysteriously malfunctioned the night before, and his old crew weren’t having any luck getting them running again. He thanked her profusely, sincerely grateful that he wouldn’t be the one among the bright lights and humming machinery, wouldn’t have to interact with the maintenance team. Instead, he was keeping an eye on Alphys while she initiated the new network, and on Sans while he made adjustments to the cannon’s firing mechanism. They were both down the hall, chatting idly as they worked.

The young skeleton had offered a few days prior to stay late at the lab when needed, and had turned out to be more help than Gaster expected, staying late into the night to finish all the work Gaster had given him, and then some. Then he had offered to come in on the weekend. He was probably just trying to worm his way out of his assignment, and Gaster couldn’t really blame him, but also wasn’t going to relent just because. It was important that they keep gathering data about the barrier, looking for any sudden or minute changes in its frequency. This would be so much easier once they could gather data from inside the lab, but at least Sans did his job.

At least he wasn’t as cheeky as Alphys, who had joked about Sans fetching coffee and correcting paperwork, calling him the ‘true intern’. Gaster held his tongue, not wanting to scold her for poking fun. He had given her the internship so she could put her schooling first, and come in on her own time. Why she needed her doctorate so badly he could hardly fathom. As brilliant as she was, she would most assuredly have a position in the lab if she asked for it. And she didn’t need the prestigious degree if she wanted the position of Royal Scientist after Gaster was gone. But she had always been a gifted student, perhaps she enjoyed the school environment too much to let it go.

He plucked at a loose thread on his sleeve and sighed. He had never enjoyed being a student. Aside from the 'impairments’ he eventually overcame, he had been a tad too rebellious, insistent on giving his teachers hell even when they were patient with him. Perhaps if he had been a bit more understanding to their position, if he had showed them some kindness, he would have had an easier time.

Well, that was in the past now. Though he may have been a lousy student, he was now a professional, and he commanded respect from others. In the end, being a good student doesn’t matter.

Remembering that he had actual work to do, he decided to stop moaning and act like the professional he was. He couldn’t stand around all day reminiscing or bemoaning his own health. There was so much to be done before the king’s visit, if the cannon were to be demonstrated. It didn’t have to be properly tuned, it just had to fire. But the firing mechanism wasn’t aligning properly, and the barrel of the cannon wasn’t complete or attached, and the power supply couldn’t be hooked up until all of the capacitors in the core were functioning properly, just in case.

He wished he could use the tiny, completed prototypes, but he wanted to impress Asgore, not just show him proof of concept. The king was his friend, and worked hard to give his citizens the hope they needed to keep going. Gaster wanted to give some of that hope back to Asgore.

He decided to fiddle around with the program they would use to adjust the frequency of the cannon, since it was something he could do quietly. Of course, it hurt to stare at his computer screen, but everything hurt. He cheered himself up by hiding a little note in the program, titling it 'Gaster’s Blaster’s Tuning Fork.’ _How professional_.

* * *

  
Sans offered to go get lunch for everyone, since his fiddling around with the firing mechanism was getting nowhere, and he was basically serving as a distraction for Alphys while she worked. At least he could talk to her with a straight face. Just looking at Dr. Gaster after the dream he had a few nights ago made him ache with shame, and he was sure it showed, even on a face like his.

_Crushes are fucking stupid, I just wanna prove I’m a competent scientist without feeling like a giddy schoolboy at my boss’s approval. I didn’t ask for this._

He was grateful Gaster had agreed to let him stay late, and work the weekend. It meant he could get more done, and he could be around Gaster. Helping him. Right. Because nothing was different, he had always admired the doctor and his work. But in person, he was just so... magnetic. When you're a kid reading a book about science, it's easy to imagine the author as some droning professor, and Gaster's writing was a little dry. But off the page, he was someone unexpected. To think someone the public held in such high regard cracked bad jokes and slept on the job. _Maybe it's best not to judge a person by their reputation_ , he thought. He was looking forward to learning more about Dr. Gaster.

 _Can't judge 'em by first impressions, either_. Although his first interaction with Alphys had been painful, after spending the morning chatting with her, she was growing on him. Her little claws tapped away at the keyboard like it was nothing, working even while rattling on about discarded human technology and animation. Apparently that oscilloscope had caught on fire at some point, and she fixed it (rebuilt it, really) with parts she had found at the dump, while marathoning some cartoon about a time traveling teenager and a dog monster, and had all repairs completed before the series was over. Sans had called that impressive, and she had insisted it was a long series.

What kind of sandwich had she wanted? Egg? He popped into a store at the edge of the capitol and grabbed three sandwiches, two bottles of soda, (extremely bad for his bones, but who could resist?) and a can of tea, for Gaster. Gaster hadn't actually asked for tea, but it was good for headaches, and it was easy to tell the doctor was in a lot of pain.

They were waiting for him in the lobby when he returned.

  
"Welcome back, Sans!" called Alphys from across the room.

"Someone stopped by for you, Sans, but they couldn't stay" said Gaster. "A Papyrus? He left this for you."

Sans groaned when he saw the paper bag in Gaster's hands. He already knew what was inside. He took the bag with a mumbled 'thanks' and handed over the doctor's sandwich.

"I didn't realize you had an older brother, he was quite charming." the doctor continued, while Sans silently handed Alphys her lunch.

 _Great, what did he say about me?_  "Actually, he's my younger brother." Sans admitted, blushing. He heard Alphys try and fail to stifle a giggle, any commentary muted by the sandwich in her mouth. Now that Papyrus had surpassed him in height, he would need to get used to people making that mistake. "Here, I thought this tea might help with your headache." He handed the cannister to Gaster and sat down with his own lunch.

"I... thank you..." Gaster said softly. "I didn't think it was that obvious."

"Thanks for not laughing at me." Sans replied, shooting an exaggerated glare in Alphys's direction. She brought one claw to her mouth and rubbed the other over her collarbone in apologetic gesture, but continued to giggle.

"Why Sans, I'm surprised you think so _little_ of me." said Gaster.

Sans brought one hand over his face and sighed. From between his fingers, he watched Gaster smile and laugh, and couldn't help but smile as well.

**Notes for the Chapter:**

> Heya, I've got a new job, so updates might slow down a bit, but I'll shoot for 2 a week.  
> Also I accidentally wrote Alphys into a chapter where she doesn't even talk. I feel bad about that. :-/


	8. Don't talk with your mouth full

**Summary for the Chapter:**

> The one were Alphys actually says something.

"So, what did Papyrus have to say?" Sans asked, sidling up to Gaster. _Please nothing embarrassing_ , he thought.

Gaster continued to chew his sanwich, hand over his mouth to be polite. "He was curious as to whether or not you're working the whole weekend. I told him you're free tomorrow if you so choose." He said, after a moment.

"Are you going to be here?" Sans scratched under his collar nervously.

Gaster gave him a look that was somewhere between concerned and reprimanding. "You should spend time with your family, Sans. I know things are rushed, but there's no need for you to be here all week." He took a final bite of his sandwich, popping the last bit of crust into his mouth.

"Well, what about you?"

"I don't have family. Not any more." Gaster said flatly around what crumbs he was still working through.

"No, I mean you're here all week. Do you ever go home?"

Gaster chuckled softly. "Sometimes. But even there I'm working on things that I could be here doing. I'm in the middle of another book, you know. I've had it in the works for two years."

"That can't be healthy."

"My first book took much longer than two years to write, Sans." he smirked.

"I mean being here all the time." Sans groaned. "Sleeping at your desk and all that."

"Well..." Gaster looked away. "If you can keep a secret, I actually keep a cot in my office down in the lab proper. I just don't usually make it down there before I fall asleep." He looked slightly ashamed. _He should be_ , Sans thought, _that's just a little ridiculous_.

Sans's eyes narrowed. "I thought you said we weren't supposed to be in the lab proper if we were inhibited in any way. Wouldn't sleep deprivation count towards that, Doctor?"

"And that's why I have the cot, so I can be well rested and ready early in the morning. We're getting off topic here, Sans. The point is that I will probably be here tomorrow, but you do not need to be. So go have dinner with your family. From the sound of it, your brother misses you dearly."

"Yeah, alright." Sans sighed. "Be safe."

He sat over next to Alphys and opened his sandwich.

By the end of the day, he still hadn't finished his adjustments on the firing mechanism, so he left a note for Juneborg detailing what he had done, as well of ideas of how to get it working properly.

Alphys had finished hooking up the network, and she and Sans were going around, checking the computers in the upper and lower lab, making sure they were all connected to each other. Gaster had gone down to his office, and Sans didn't see him for the rest of the evening. Alphys went down to let him know she was finished, and Sans headed home for the day.

Once he was home, he called his brother. "Hey, Papyrus, ask mom if I can come over for dinner tomorrow night? Yeah, thanks. Okay, I'll see you then. Love you, too."

* * *

 

Monday morning was off to a good start. Sans arrived at the castle and set up the oscilloscope and monitoring equipment, this time by himself. He sat down near the machinery with a folder of paperwork Gaster had given him on Satyrday evening, and got to work.

About an hour in, Alphys came to see him. She was carrying a backpack and a clipboard.

"H-Hi Sans! How's it going out here?" She asked, brightly, setting the backpack down next to him.

"Oh, uh, it's alright. Don't you have class today?"

"Yeah, I um, I took off from my first class just for today, I needed to hook the scope up to the network, remember?" She set down the clipboard next and pulled a few small devices from the backpack. "Here, hold this for me?"

She handed Sans a small plastic box with a bunch of ports and buttons on it. "Yeah," he replied, "I just figured you'd come after school." He watched her pull several cords of varying length from the bag.

"It's fine, I've got a tape recorder set up so I can listen to the lecture later. And this should only take twenty minutes. No sense in you wasting another day out here, right?" She took the box from him and set it down between the scope and the monitoring equipment, then began plugging the cords into various points on the machinery, connecting from the scope to the monitor, to the box, and back. Sans watched with fascination. "Can you plug this into the power source for me?" She asked, holding up one final cord to Sans.

"Sure," he shrugged, and turned out of the room to plug it in just outside the door. When he got back, Alphys had hooked a small keypad into the box and was typing out something.

"Oookay," she said, "we should be good to go! So um, if you ever need to reset this thing..." She held the box up at an agle and Sans leaned in for a better look. "Just hold this button down right here, and flick this switch off, then on again. And if you need to disconnect it, well, the ports are color coded, so you shouldn't have a problem with that. Oh, wait! You're not colorblind, are you? I'm so sorry, I should have asked that f-first!"

"Nah, I'm good. Full-color vision. I think."

"Oh, thank goodness. Then that's all! You should be able to access the monitor from your computer in the lab's office."

"That's all?"

"Yep!"

"That was fast, Alphys. Thank you. I'm glad I won't have to schlepp out here every morning and hook this thing up."

"Yeah, this should save you a lot of time." She said as she scribbled something down on her clipboard. "So, uh, before you head back, do you wanna grab a snack or something with me? My next class isn't for another hour or so, and Doctor Gaster won't care as long as you bring him something back."

"Sure, where to?"

"There's a cute little cafe just a few blocks from here, follow me." She put on her backpack and Sans followed her out.

They strolled side by side down the narrow streets of the capitol, making small talk about the weekend, the weather, and the work they were doing. They arrived at the cafe, ordered some tea and half a dozen turnovers, and sat down at a small table in the corner.

"So wait, how long have you known doctor Gaster, then?" Sans asked.

"Since I was six? Seven?" She said, pulling a pastry out of the box. "Definitely before he became the royal scientist. He used to teach MSL, and held a speech therapy class."

"Woah, I had no idea. Why speech therapy?"

"I had a really bad stutter when I was younger." she admitted shyly, "w-way worse than it is now."

"Oh... Um, I meant why was he teaching the class?"

"Oh, sorry! He taught them because he had a lot of experience dealing with that kind of stuff, I guess? He had severe speech impairments when he was younger, and I think something with his hearing, too. So for most of his childhood, he communicated through MSL and writing."

"Really?"

"Y-yeah. I mean he still does, sometimes. I'm surprised you never noticed. And he wears a hearing aid, too. It's tiny, so you can't see it, but it's one he built himself. He told us that was the whole reason he pursued a career in science, because he enjoyed designing and building useful technology."

"That's really cool. He never mentioned that in any of his books."

"There's a lot of stuff he doesn't mention in his books. You should ask him sometime what he thinks of the old royal scientist, Doctor Marlick."

"What? He had nothing but praise for them, didn't he? He even mentions them in the dedication section of 'String Instruments and Instrumentalism'!"

Alphys smirked and took a sip of her sencha. "Do you know what sarcasm is, Sans?" She asked. "Marlick had no idea what they were doing as royal scientist, and Gaster fought with them all the time about it. He used to ramble on about them in class, and use them in example sentences that weren't very nice."

"Wow, that's petty."

"I know, right? No one was expecting Marlick to nominate him as the next royal scientist after they left. It meant he had to stop teaching, so he could be in the lab full time. I really miss those classes. He made them kind of fun. He told me I was smart, back when no one else thought so. I started working with computers and building things because I wanted to be the next royal scientist after him. And he told me I could do it. I'm glad he pushed me, but now that I'm older, and there's actually a chance I might be his nominee? I don't really want any of that responsibility!" She laughed nervously. "Don't tell him I said that, though."

"Is that why you're just interning at the lab?"

"Pretty much, yeah. I mean this cannon's a great idea, and it should work. B-but if it d-d-doesn't... I don't think I could come up with any better way to break the barrier. I don't think King Asgore would appreciate a scientist who just shrugs and says 'welp, I've got nothing!' You know?"

"I get what you mean. Being the royal scientist is a huge honor, but it also means a lot of pressure on you. I don't think I could ever be a figure head like that, either." He popped a piece of turnover into his mouth. "But so far no one has found anything that might bring down the barrier, so at this point, it's not like anyone's expecting anything. And you could still do a lot of good for people. Marlick's research gave a lot of insight to what souls are made of, and with the core running, people all the way out in Snowdin have a reliable source of power. So it wasn't all for nothing."

"I suppose that's true. I just don't want to let anyone down."

"Well, let's make sure this cannon works, then you can be royal scientist on the surface, yeah?" He held his cup in the air towards her.

"Yeah, on the surface." she picked up her own cup and brought it slowly up to his, knocking them carefully together.

**Notes for the Chapter:**

> I need to space these updates out better. :-y  
> I also need some advice. I've got something very ~saucy~ coming up, and I don't know whether to put it in this story and change the rating, or post it on its own. One of the main problems is that I was hoping to stay pretty vague on Gaster's appearance, so people could just roll with whatever headcanons they have on what he looks like. But I already messed that up a little bit, and I kinda want to get a bit... descriptive when that part comes up. I mean, it's gonna get written, either way. But I want people to have the ability to skip over it if they so choose. I'm also trying to decide whether to draw Larkeet, Juneborg, and Wickett, or whether I should leave them up to the readers' imaginations.  
> What do you think?  
> Also, if anyone needs to reach me for questions or anything, you can message me on tumblr:  
> ice-cream-salad.tumblr.com


	9. Come with me, for science!

**Summary for the Chapter:**

> Let's do some actual work this time. Or something.

Back at his desk, Sans checked to make sure that the scope and its monitor had in fact connected properly to the lab. Everything seemed to be in order, Alphys had done a fantastic job. There was even a little diagnostic tab that could display any errors within the scope itself, letting him know whether it had malfunctioned. He would have to thank her again the next time he saw her.

He set the remaining crabapple turnovers from the cafe onto Gaster's desk, and rode the elevator down to the lab proper. One of the memo screens in the corridor had a message for him:

' _Sans, thanks for your notes on the firing mechanism, but the coil will need to be made from a different kind of metal if we make it to those specifications. I don't know if there's anything that pliable that can withstand the amount of heat to be generated, but if you've got any ideas, I'd love to hear them. Come see me when you get the chance. -Juneborg.'_

Welp, she was probably right about that, but he didn't have any ideas at the moment about what kind of material they'd use instead. He thought about it as he walked down the halls towards the cannon room. Up ahead, he could hear Professor Wickett's voice.

"And I'm telling you, the barrier doesn't absorb or block things that try to go through, it repels them! King Asgore knows that better than anyone, Gaster! If we fire this thing at the barrier, there's a good chance the beam'll bounce back and vaporize the cannon and us! We'd be better off trying to use one of the human souls to break it down. At least we know they can get through."

"That's why I'm trying to get his permission to analyze the human souls, Wickett!" Gaster snapped back, his voice strained. "But before I can do that, we need to show him we're serious about this, impress him! Instill in him the belief that we're confident this will work."

"It won't. It would work if the barrier were a physical object, Doctor, but it's not. It's magic, human magic, and it doesn't play by our rules! At least admit that it's a huge risk, and you've got my support! If you can't admit that much, I'm off this project."

"I-Yes, it is a risk." Gaster sighed. "There's a chance it could kill us, there's a chance it could short out the core, there's a chance the beam will pass right through the barrier instead of doing damage to it. But There's also a chance it could work, and I think that's worth pursuing. Don't you?"

Wickett looked unimpressed, standing there with his arms crossed and a bored look on his face. "I think you should let Asgore know about the risks, he has the right to know what could go wrong. And if he's still okay with it after knowing all of that, then I'm with you. In the meantime, maybe we should demonstrate with the prototype cannon, since it's already in working ord-"

"Now you're just being ridiculous!" Gaster huffed. "That little prototype cannon is just proof of concept. It's not going to impress him!"

"All we need right now is proof of concept! And you've tested the prototype already, haven't you? It's safe to fire in a confined environment, whereas I'm pretty sure this thing won't be."

"Enough! We will get this cannon in working order, and we will fire it as a demonstration for Asgore. I will leave it up to you what type and amount of magic will be appropriate to use, but that will be the extent in your say in this, Wickett. Do I make myself clear?"

"Whatever you say, Doctor." Wickett snarled, his eyes narrowed.

Gaster rubbed the sides of his forehead. "Sans, was there something you needed?"

Sans jumped at the mention of his name and stepped around the corner. "Oh, um, Alphys hooked my scope up to the lab, so now I'm here? What would you like me to do?"

Gaster sighed. "Good, excellent. I think Juneborg wanted to go over your notes with you, so go take care of that. I'll be in my office if anyone needs me."

"Alright, thanks." said Sans, stepping aside as an irritated Professor Wickett sidled past him. He followed Wickett down the hall to another section of the lower lab, where Juneborg was waiting. The room was scattered with machinery and tools and blueprints. At first glance it looked cluttered, but the tools were actually arranged by size and evenly spaced out, and the pieces of machinery were stacked around the blueprints they belonged to. Not a bad system.

Juneborg was clicking and humming to herself, her attention on the small machine in front of her, and the tiny screwdriver she was using on it. One of her antennae twitched as Sans and Wickett approached. "Juuuuuust a moment, please." she said, slowly pulling a small screw from the machine, she placed next to two others of the same size on the table next to her.

"Okay, there we go!." She turned to face them. "Sans, great news: Dr. Gaster found another coil that will fit those specifications, it just needs to be trimmed. And you mentioned something in your notes about the beam possibly spreading outwards, so Professor Wickett here suggested-"

"We can place some reflectors in the barrel of the cannon that will re-center the beam if it spreads out far enough to hit them." he said.

"Thank you for **interrupting** , Professor." Juneborg replied in a mockingly happy tone.

"My apologies, I'm gonna go sit down." He wiped a droplet of wax from the corner of his jaw as he crossed the room and flopped down in a chair by an empty desk.

"Well, that's great news for sure." Sans said, shrugging. "That should keep the beam more focused, right? Will the barrel need to be altered at all to accomodate for the reflectors?"

"That shouldn't be necessary." she said, pulling a small notebook from the pocket of her labcoat. She opened it to a marked page and looked over it for a moment before continuing. "No, we won't need to make adjustments to the structure of the barrel. The reflectors should be thin enough to just sit in there. We'll need to make sure they're set in firmly, though. We're not gonna want them shifting around. Their position needs to be precise. I'll draft up a diagram of what we've got planned once I'm done with this." she pointed to the small machine she had been dissembling.

"Sounds like a plan." he replied, leaning on the table behind him. He glanced over to Wickett, who was slumped at his desk, holding pen to paper, but not actually writing. "Hey, professor," he called, making his way slowly over to Wickett. "I've got a question for you."

"Yes, Mr. Calibri?" asked Wickett, turning to face the skeleton.

Sans could feel the tension in his voice. "It's just Sans, please. Anyways, I couldn't help but overhear your... conversation with Doctor Gaster earlier. It made me wonder, does the barrier really repel all kinds of monster magic?"

"It's supposed to, yes. Why do you ask?"

"I was wondering. Do you know for sure if it repels blue magic? Like the kind the royal guard use?"

Wickett drummed his fingers against the desk. "To my knowledge, no one's ever tested such. I think I see where you're going with this. Blue magic's supposed to move through immobile objects, and the barrier is, after all, stationary. But it's also dense, and there are coils of magic travelling through it constantly. I don't think even blue magic could make its way through."

"Right, but it wouldn't need to go all the way through, though. Would it? I mean if it gets into the surface of the barrier at all, wouldn't that be enough?"

"It... might, actually, yeah. It passes through most magical shields, so there's a chance... I'm not certain, though. We'd need to test it to be sure."

Sans felt a small rush of excitement. "Well, why not test it out, then? We've already got a scope hooked up, and the frequency readouts have been pretty much constant so far, with no interference. Maybe we should see if anything CAN interfere with it?"

"You talk to Gaster, then. Get his approval on it. I'll get the paperwork ready."

* * *

  
"Excellent, Sans." said Gaster. "I can't believe he agreed to it. And it's true we haven't measured any interference on the barrier since we started monitoring it. Will you be running this experiment today?"

So formal. "If that's alright. Should we just grab one of the royal guards and have them take a shot at it, or...?"

"See if you can find two or three of them that aren't busy. I'll call Asgore in a moment and ask him if he can spare anyone. While you're out there, have them try some orange magic as well. Especially if the blue has some effect. We already have reports verifying normal magic attacks do nothing, so don't worry about that."

"Alright, so two or three guards, orange and blue magic, anything else?"

"Make sure you take notes. Record any change, or lack of change, and report back to me at the end of the day."

"Roger, Wickett and I are gonna make sure Juneborg doesn't need anything else, then head out. See you in a few hours." Sans said, turning to leave.

"Ah, wait just a moment."

Sans paused, mid-step. "Yeah?"

Gaster reached out and gently tugged at the shoulder of Sans's labcoat. "You had a loose thread." he whispered, "Sorry." He held the thread up briefly for Sans to see, before flicking it away.

"Thanks." Sans relpied. He chuckled nervously and turned away.

* * *

 

It had been eight weeks since Gaster had spoken directly to Asgore. Eight weeks since the awkward (but brief) meeting where he had asked permission to hire a few new scientists to the lab. Permission had of course, been granted. And surely Asgore would bear him no ill will. Sometimes friends lose contact. It's hard to keep in touch in a busy, fast-paced world like theirs. Sometimes they only speak four times a year. That says nothing against the strength or the quality of their friendship.

Too bad this was a business call.

"Hello, Gaster, old friend!" said Asgore as he picked up the line. His voice had the same sweet, heavy tone it always had. Like honey being poured from the speaker. "I was hoping you'd call soon. what's on your mind? Are you excited for the quarterly visit?"

"Asgore, Hello!" Gaster chirped back. He hoped he wasn't laying on the fake cheer too thickly. His head was killing him. "I am all to eager for your visit to the lab! But I called to ask you a quick favor."

"Of course, friend. What do you need?"

"I'm sending two from my team down to run a little experiment on the barrier. I was wondering if you could spare a few of your guards to give them a hand?"

"I absolutely can! Things have been pretty quiet around here, you know. It's kind of nice. Anyway, how many?"

"Just two or three, but they need to be able to wield both orange and blue magic. We just need to know if it has any disruptive effects on the barrier."

"Oh, that sounds... neat? Hey, you know, I can wield both. Should I go down and give them a hand, too?" he chuckled.

"I-I don't think I can do anything to stop you, if you're not busy, but... No, just the guards will be adequate."

"Oh, alright, if you say so. Say, Gaster? How have you been? It's been a while, you know?"

Gaster's stomach was twisting and contorting into new shapes, and some unseen force was repeatedly slamming a door into his head. He hadn't been this stressed and nervous since he began building the core, and he knew the core was going to work. He honestly wasn't so sure about this cannon, and the more effort his team put into it, the more ridiculous it felt.

"I'm quite alright, Asgore. But I've got a lot of work to catch up on over here. Perhaps we can chat next week, when you come for your quarterly visit, yes? I'm sure you're busy, too."

"Oh. Um, sure. That sounds nice, let's do that." Asgore's voice still held that cheery tone, but the sincerity behind it was gone. Gaster wanted to humor him, to talk for hours like they used to, but things were a bit different now. Things had been different for a long time. "Have a good day, Dr. Gaster. See you next week."

"You too, your majesty."

 

 


	10. Nine Thousand and One

**Notes for the Chapter:**

> I just want to start this out by saying that I don't get migraines, but I feel really bad for people who do. I bet they're really awful, and you'd do ANYTHING to get rid of them, right?  
> Also, Guine is pronounced 'gween'. :-y

"Alright, everything's stable. Ready? GO!"

At Sans's signal, a large blue pinwheel flew through the air, lodging itself deep in the surface of the barrier with a gritty sound before it slowly dissipated.

"Woo! Nice one, Pango!" Shouted one of the three guards. Pango scratched the back of their neck and shrugged.

"Nah, I think Knight Knight did a better job. Hers didn't disappear as fast, ya know?"

"Yours certainly went in much deeper, even if it didn't last as long." Knight Knight assured them.

Sans ignored the innuendo while the guards laughed among themselves, and looked over the readout from the oscilloscope. There had been a slight shift in the sound of the barrier, as with the previous attack, but again within ten seconds, the frequency returned to normal. A good sign. He also noted a huge spike in the heat and energy the barrier was producing. A good sign? Wickett leaned over to read what Sans had written onto the clipboard with a nod of approval.

"Alright, Guine? You're up." said Wickett, gruffly. "Show us what you got."

The last of the three, a red plant monster, approached the barrier as the other two stepped away. He crouched down, breathing steady, eyes focused on one point ahead of him. "I'm waiting for your signal." He whispered.

"Okay, whenev-"

With a shout, Guine leapt up and sent a volley of blue flowers at the barrier. Each flower split into a beautiful array of scattered petals, swirling around in an intricate pattern before dissolving just under the surface of the magical forcefield with a sound like sand running over itself. Dazzling, but according to Sans's readings on the scope, this one was the least effective yet, almost no changes showed up on any of the devices. He made note of this. Strong, singular blasts were probably going to do a lot more than a bunch of scattered shots.

"Guine, you're such a showoff!" Pango laughed. "There was no need to be so dramatic!"

"Hey," he countered, turning his head away, "They asked for our best, and that's what I gave them. If my magic is beautiful, that's just a bonu- Oh, your majesty! Greetings!"

All eyes turned towards the door, where Asgore was leaning in, watching them from halfway behind a wall. He flinched when he was spotted. "Oh, I'm sorry!" He bellowed. "I-is it okay that I've been watching? I know this is all supposed to be a bit of a secret until your presentaion, but..." He stepped into full view, twiddling his thumbs and looking over the crowd in front of him. Sans had never seen anyone so large and regal look so timid.

"Uh, come on in, Your Majesty?" Sans said, shrugging. What was he supposed to do, turn the king away?

"Asgore, you should totally take a shot at this!" Pango cried out, jumping up and down excitedly. "I bet you could send a blue attack _at_ _least_ halfway through the barrier!"

"Oh? Well, I certainly would not mind taking a shot at it."Asgore chuckled, "It wouldn't interfere with your experiment, would it?" he asked, turning to the scientists.

"I personally would love to see what you can do, sir!" said Wickett. "And I'm sure it wouldn't interfere, if anything you would be helping us greatly."

Asgore's face brightened and he immediately summoned his weapon; a huge, red, glistening trident. "Let me know when you are ready, then." He said, smiling.

"Heh, go for it." said Sans. Everything had gone back to baseline almost immediately after Guine's little show.

Asgore took a deep breath and turned solemnly toward the barrier, gripping his trident tightly. The three guards stepped away to give him space but they never took their eyes off of him. He widened his stance and pulled the trident behind him, taking a deep breath. The motion of his swing began in his toes, gripping the floor beneath him. The muscles in his legs tightnened, allowing him to brace himself as the traveling tension rose to his abdomen, up his back, and into his shoulders, where it pushed itself out into his powerful arms. Sans caught a brief flash of bright blue in one of the king's eyes as he swung forward with a roar, flinging an arc of blue magic from the end of his trident. The arc shot forward into the barrier with a sound like scraping gravel, beginning to dissolve almost immediately upon contact, but continuing its motion until it was about 10 feet deep. Sans watched, stunned, counting the seconds. Sixteen, seventeen, eighteen...

He chanced a glance down at the scope, which looked like it was having a fit at the sudden change in energy. Twenty-four seconds in, and the arc still hadn't fully dissolved, and the pitch was still changing. The temperature readings were almost at the limit of what they could measure. He'd have to bring that up to Dr. Gaster at some point before they tested the cannon.

"Well," huffed Asgore, "how was that?"

Sans looked up, speechless. The guards were all exchanging wide-mouthed stares.

"That," said Wickett, "was **exactly** what we need."

* * *

 

Sans was grateful they hadn't let Asgore fire an orange attack at the barrier. The bright orange orb Knight Knight unleashed had shattered before bouncing back out at them, startling everyone, and passing only inches away from one of Sans's machines. That had been enough excitement for all of them, and they called it quits shortly after making sure everyone was alright.

He and Wickett thanked everyone for their participation in their little experiment, and Asgore thanked the pair of scientists for allowing him to blow off some steam. Sans felt sorry for anyone, past present or future, who managed to piss off the king. Sure, he was a lovable block of fluff who would never hurt anyone, but _boy golly gee_ , _he could_ _if he changed his mind._

The two of them talked on the way back about what this meant for them and the cannon.

"There's still a chance the barrier will reflect any part of the blast that isn't blue magic," Wickett assured him. "But if we do manage to match frequencies, firing a focused, continuous beam, we might actually be able to overload it. Next question is 'Will we be able to break it permanently?' It only took a few minutes for it to recover from Asgore's attack. We'll probably be dishing out something much more powerful, but there's really no guarantee it's not gonna heal itself. Are we just gonna push as many monsters as possible through the damn thing before it closes up? Or do we send Asgore through with the cannon and a few good monsters, and hope for the best?"

"I guess we'll need to make sure we plan for whatever happens." Sans said solemnly.

"I want to get behind this project, I really do, but I'm also a firm believer in human magic being the only thing that can really disable the barrier." He thought for a moment. "Which is kind of ironic, since monster magic is so much stronger. I guess that's the trade-off, power for permanence."

"Human _souls_ get both though, right?"

"Unfortunately for us, yeah."

* * *

 

They returned to the lab with a couple of hours left in the day, which they used to write a short report that summed up their little experiment. It hadn't exactly adhered to the scientific method, but all they had needed was proof that the barrier wouldn't reflect blue magic, and they had it. As a bonus, they had data from the monitoring equipment that showed exactly how much this magic interfered with the near-constant energy of the barrier. Wickett put the report together on his computer, with Sans reading him the data.

Juneborg came up to the office shortly after their arrival and sat down at her own desk, bringing up a CAD program on her computer. She asked them how their experiment had turned out, and if the cannon would be firing blue magic after all. Sans and Wickett took turns relaying what had happened, reading bits of the report, and describing in detail Asgore's attack on the barrier. Wickett asked if she had made any progress on the firing mechanism, aaaaand she changed the subject to the reflectors, and how she was plotting out their positions at the moment. Sans laughed and sat down at his own desk to type up his daily report, which was finally necessary now that they had recorded some interference.

The three of them chatted idly while they finished their work for the day. Juneborg printed out her draft for the placement of the reflectors, and left it on her desk as she wished them both a good evening. Wickett yawned and wished her the same.

Sans got an idea. He offered to print off their report and take it down to Gaster himself, which Wickett gladly accepted. _Not surprising, considering their earlier interactions,_ he thought. Once Wickett had headed out, Sans's pulse began to race. Now it would just be him and Dr. Gaster, alone in the lower lab. He drummed his fingers against the desk impatiently while he waited for the printer. _Come on, it's a two page report_ , he thought. _There's no reason it should take this long._

He grabbed it immediately once it was finished, and rushed to the elevator. On the long ride down, he scolded himself for feeling so giddy. There was no need, this was strictly business. He would hand Gaster the report, tell him how the experiment had gone, and then... then what? Make small talk? Ask him out to dinner? No, that would be way too forward. But not weird, right? Alphys had asked him out to lunch, it was something co-workers did.

He tugged absentmindedly at his collar, pulling a thread loose on the seam, making sure it was noticeable.

The elevator dinged and he glanced up at the memo screens briefly, making his way quickly down the hall. There was an update from Juneborg about the coil being trimmed and fitted, and a reminder from Alphys to make note of any network problems so she could fix them. Nothing from Gaster.

He continued down the halls, looking around as he went. The doctor was probably either with the cannon or in his office, but Sans didn't know for sure, and he definitely didn't want to miss him on his way out. He turned and headed down towards the cannon, trying not to look it in the eye as he approached. That thing was at least a hundred percent creepier with no one else around. Sans checked the hallway behind him, and all around the cannon. Nothing. That left the office for sure. He gripped the report tightly, taking a deep breath to steady himself as he raised his bony hand to knock on the door.

But as he took that deep breath, he heard an echo, and then another. There was heavy breathing coming from the other side of the door. Sans froze, his hand in the air, unable to bring it down. He held his breath, listening carefully. The breathing was accompanied by other noises, the sounds of rustling fabric, the squeak of a cheap mattress spring. A smothering heat rose within him, burning his cheekbones. _Those sure are the sounds of a resltess sleeper_ , he tried to tell himself. Then came a soft gasp and a moan and Sans pulled his hand away, covering his mouth. His brain was telling him to get the fuck out of there, but other parts of his body were begging him to stay and listen to a symphony of private sounds he definitely should not be hearing.

He picked up his feet slowly, backtracking as quietly as possible. As much as he wanted to stay, he really didn't want to be around when those noises stopped. He set the report down gently on one of the tables next to the cannon, tiptoed out of the room, and then he ran, only catching his breath once he was safely inside the elevator.

 _WELL!_ he thought, _THERE IS_   _NO WAY I'M NOT GONNA BE THINKING ABOUT THAT FOR THE REST OF THE NIGHT!_

And what a long night it was going to be.

* * *

Gaster relaxed for the first time in what felt like weeks, relief seeping into him like syrup. _Thank goodness_ , he thought, _once my migraine clears away I might actually get some sleep._ He lay there for a minute, catching his breath, staring at the ceiling as relaxation turned to drowsiness. He was torn between wanting to rest right away, while he was still comfortable, and the need to get up and drink something. That tea Sans had given him sounded perfect, but he had left it in the upper lab, and that meant a long elevator ride up and back down, and by then maybe he wouldn't even want it anymore.

He decided a compromise was in order, and he would get something from the vending machine. Pushing himself up slowly, he righted his clothes before unlocking the door and stepping out.

On his way past the cannon, he spotted some lightly-crumpled paper on one of the worktables. Had that been there earlier? He picked it up and looked it over. _Ah, this must be the report I asked him for_ , he thought absently. _I suppose we'll need to alter things a bit then_. He set the papers back down and was halfway to the vending machine when he realized what time it was. Sans and the other scientists must have only left recently.

_Oh no._

He rushed to the elevator and got inside, tapping the 'UP' button furiously, his pulse raced the whole ride up. There was no way Sans had been down there, Gaster hadn't heard anything outside his door.

He jumped out as soon as the doors opened. "Sans?" He called out "Are you still here?"

There was no answer. He rushed upstairs and checked the office. No one. A quick look at the clock told him their workday had ended less than thirty minutes ago. He brought a hand to his face, mortified. There was no way Sans hadn't been down there when he- no, why????

The sense of calm he had achieved earlier was quickly evaporating, and he could feel his headache creeping back.

 _So much for a good night's sleep_ , he thought.

Tomorrow was going to be hell.

 

**Notes for the Chapter:**

> Yyyyeahhhhh, so i'm sorry? Maybe?


	11. Holdup

**Notes for the Chapter:**

> hhhnnnNNNNNgggggGGGGG some really cool people drew a couple of the OC monsters for this story!(Both images are SFW, but the blogs that posted them are NSFW)
> 
> Wickett, by Pornpyrus:  
> http://pornpyrus.tumblr.com/post/138432967166/idk-what-im-doing-read-something-you-cant-measure
> 
> and Juneborg, by Pepperchan:  
> http://pepperchan.tumblr.com/post/138372868483/doodle-for-friends-story-thing
> 
> Poor Pepper was bribed into it, but i'm still so freaking giddy. <3

Sans stared at himself in the mirror, checking out his cheekbones. They looked fine. He briefly allowed himself to think about Gaster, about what he had overheard last night, and gratefully noted that while he was visibly blushing, it wasn't all that noticeable. Good for him, because it was going to be difficult to put out of his mind if he wasn't kept busy. The plan was to just not say anything. If Gaster did bring it up, Sans could play dumb. _Hmm? Oh, I thought you had gone home for the day, and I was in a hurry,_ He thought to himself, _So I just left the report there where I knew you'd find it._

He took his time walking to work. For once, there was no point in getting there early and being there alone with Gaster. Making it just on time, he entered the lab and went straight for his desk. His first task of the morning now was to check on the scope. Wickett was already in the office when he got there, sitting at his desk and typing something out. Unfortunately, Gaster was there, too, leaning up against one of the file cabinets. He looked like hell, with huge bags under his eyes and a sour expression. Had he been up all night?

"Good morning Sans." Gaster said tightly.

"Morning, Doctor." Sans mumbled in reply. He sat down slowly at his desk, avoiding any eye contact, quickly opening his connection to the equipment at the barrier. All the equipment was running smoothly, and the frequency had returned to where it had been before their little experiment yesterday. He scrolled back and forth through the readings for a while, trying to ignore the sensation of being watched.

Finally, Gaster broke the silence. "I found your report this morning, by the way. I'm glad your experiment was a success."

Both Wickett and Sans turned in their chairs to face him.

"If we're using blue magic, we'll need to make sure the reflectors will actually work with it. Wickett, I'll leave that to you. Sans, I'll need your help finishing the firing mechanism and attaching it. Juneborg's putting together the shell. I'll finish and attach the power supply once you're both done. I'd like us to be able to do a test fire by the end of this week, so that we're ready for next Tuesday. Does that sound reasonable?"

"Yes sir." Sans mumbled. Wickett nodded.

" **GASTER!!** " a shrill voice called from downstairs. All three of them jumped.

"I'm up in the office, Larkeet." Gaster called back.

"You need to learn to answer your damn phone!" Larkeet yelled as she huffed and stomped up the stairs. "I can't be running all over the place all the time just to speak to you!" She arrived at the top of the stairs looking positively ruffled.

Gaster stood up straight. "I take it you're finished fixing things over at the core?" He asked, laying sweetness over an irritated tone, crossing his arms.

"We should never have left that idiot Poma in charge. The capacitors are back up and running, we figured out what went wrong but you're not going to like it. Sorry for the shouting gentlemen," She sighed, turning to face Wickett and Sans. "Here's a tip though: If you ever need to reach Doctor Gaster? Just call the lab and leave a message on the landline. He **NEVER** ANSWERS HIS CELLPHONE!"

"Yeah, some things never change." Wickett groused.

"Anyways." Gaster interjected. "What went wrong?"

"I'll explain on the elevator." Larkeet said, brushing at the feathers on her cheek "Let me get some coffee first."

"I'll join you. Sans, Wickett, I expect to see you down in the lab proper shortly."

* * *

  
The firing mechanism wasn't a very complicated device, but it was giving everyone hell, refusing to actually fire, or even spark. The smaller mechanism they had pulled from the prototype worked perfectly, and they had based this one off of it. There was no reason it shouldn't work. Sans thunked his head on the desk in front of him. I'll bet Juneborg is all to happy to not be dealing with this right now, he thought.

"Still not working, huh?" Larkeet asked, approaching from behind him. Gaster sent me over to see if i could help you out."

"Thanks, but I don't need help." Sans griped, head still on the desk, "I need a miracle. Pretty sure changing the coil didn't actually help anything."

"Well, I'll just pretend to help you then, I need to relax for a bit, then Dr. Gaster wants me to double check his code for the tuning program, because something's not quite right there." She hopped up on the desk and sighed. "Don't ever become the royal scientist's assistant, it's such a pain."

"Sounds like it." He removed the coil from the mechanism and twirled it around in his fingers. "So, what went wrong over at the core? Did something overheat?"

"Yeah, but that's not even the start of what went wrong. Some critter got into the controls for one of the systems and started... eating things. I shouldn't be surprised, we've had this little pest problem for over a decade."

"Wait, really?"

"Yeah, we're pretty sure it's a dog, but it'd have to be a tiny one to get into the places it does."

"A dog?" A shiver ran up Sans's spine. He heard the coil hit the desk and roll off before he felt it leave his hands.

"It's frustrating for sure. Gaster thinks it's always the same white dog, swears it's sabotaging him. Paranoid thinking, but he's got a point. Every time we find its trail, it sets us back quite a ways."

Sans reached down and picked up the coil, dusted it off and put it back in place with a click.

"I guess we should have been expecting it, it's been a while since the little mutt has gotten into something. Anyways, he was obviously pretty ticked when I told him, but I guess there's something else bothering him too? He looks absolutely ragged. I wouldn't do anything to piss him off, you know? ...You okay, kiddo?"

"Hm? Yeah." Sans whispered, giving his skull a quick shake. He flicked the trigger experimentally. It sparked. "Woah."

"Oh my gosh! it worked?" Larkeet exclaimed, "That's fantastic! What did you do?"

"I-I don't know?" Sans answered, "I think the coil was in wrong, all I did was put it back in and now it works." He flicked the trigger once more, just to be sure, again, it sparked. Unbelievable.

* * *

"Fantastic!" exclaimed Gaster, looking the mechanism over. Sans watched he expression on the doctor's face, shift, eyes locked on the small piece of machinery in front of him. He was smiling. Something in Sans's ribcage felt lighter, until Gaster turned to him, with a less-than-pleasant look on his face. "Why don't you help Juneborg with the shell, then? I'm sure she could use an extra pair of hands."

He played assistant for the next several hours, handing June tools when she needed them, holding things down so she could weld. Wickett had already fixed the reflectors, and Sans helped her put them in place wher they would be attached. It was simple busywork, not enough to keep him properly distracted. Every half-hour or so, he would catch himself staring at Dr. Gaster, but would force his own attention back to what he was doing. Finally, Gaster was the one to catch him.

"Is there something you'd like to say to me?" Gaster whispered from behind him. If Sans had had skin, he would have jumped out of it.

"Yeah!" Sans yelped, before he had time to think. "Do you wanna go to lunch with me?"

Gaster's eyes narrowed. "Sure," he said thinly, "We leave in ten minutes."

**Notes for the Chapter:**

> Alsooooooo, sorry for the short chapter, the next bit is gonna get a bit too long, so I decided to split it. :-T I really hope that's okay. We're getting closer and closer to the little hand-jive I have planned out, and I'm getting nervous. But if this thing's gonna get freaky and weird and stuff, it might as well go all the way, right?  
> To make up for it, I'll try to have the next chapter up on Thursday, instead of Saturday.


	12. Okay, so two physicists walk into a restaurant...

**Summary for the Chapter:**

> and one turns to the other and says:

"So, these spring rolls are pretty good, huh?" Sans asked sheepishly. Gaster chewed the small bite he had taken, silently. Sans looked out the window next to them. "I've only been here a few times, but these things are just too darn good to stay away from, you know?" He picked one up and chomped the end off, covering his mouth with his hand so as not to be rude. As a skeleton, he had no choice but to chew with his mouth open.

"Why don't we just get to the point?" Gaster snapped in a hushed tone. He set the roll he had been nibbling on back down on his plate. "I know I acted in an unprofessional manner, and I know you know. Who are you planning to tell? Because blackmail won't work on me."

"Woah, I'm not telling anyone, trust me." said Sans. "I wasn't even going to bring it up unless you did. Do you really think I'd try and blackmail you?"

"You seem like the type." Gaster mumbled. "Eager, a brown-noser, probably willing to worm your way up if necessary."

 _Wait, what?_ "It's not like there's much of a ladder to be climbing here!" He countered. "There're like, five rungs." _Well, I am at the bottom of that ladder, I guess. Even the intern is more important, more crucial to the lab._ "And I don't even have a nose. I can't believe that's what you think of me." It felt like a knot was forming in his throat. Hadn't Gaster been the one to say he had a lot of potential? When had that changed?

"Well, maybe you should think about how others perceive your behaviour. Your eagerness reads as over-reaching to me."

"I was just trying to impress you, because I... well, I admire you." He hoped against all hope that he wasn't blushing.

The doctor's eyes narrowed. "Flattery's not going to get you anywhere, Sans."

"Why are we acting like I'm the one in trouble here? You're the one who- look, I'm sorry I caught you with your pants down, but why were you even- why there at the lab? I mean I guess you basically live there, but-"

Gaster cut him off, glaring. "No! I will apologize for my inappropriate behavior, and I can assure you it won't happen again. I do not owe you an explanation." He rubbed the side of his head, sighing.

Realization dawned on Sans, not like a sunrise, but more like a flashlight being shoved in his face. "Ohh!" He whispered. "It's your head isn't it? Man, that makes sense. I mean it was either that or your argument with Wickett got you all flustered, right?"

His joke fell flat. Gaster picked the roll back up and finished it off with one bite. He stared at Sans silently, taking his time to chew. Eventually, when Sans said nothing else, Gaster swallowed and spoke again. "I took _five minutes_ to myself, to try and relax, so that I could get a good night's rest. The workday was basically over, I assumed you and everyone else had gone home. It's not like this is something I've made a habit of, I'm just on edge twenty four-seven right now, and it won't stop until Asgore leaves the laboratory with a smile on his big furry face. And I can't take it, this is the most important thing in my scientific career. an attempt at bringing down the barrier is the whole reason Asgore hired me as Royal Scientist, twelve damn years ago. And just now am I getting around to it, and I am frightened that it won't work, that we won't be ready, or that he may even reject this plan. After this, I am out of **tangible** ideas. Last night, for a few minutes, I was able to relax for the first time in weeks and then, just like that-" he took a deep breath, flicked one hand in the air, "-it was gone. And I don't want to blame you for that, but- but you really have the _worst_ timing imaginable! Now? Now I'm tense and ashamed and still tired as hell!"

"Wow. I'm... that really sucks. But, I mean, I know you're stressed, and that's part of why I keep offering to help and stay late and everything, so that maybe you won't have so much to worry about. That's why I got you that tea and... I'm sorry. If there's any way I can make it up to you? I could help you relax, maybe?"

"You can help by keeping your mouth shut about this."

"Okay, but still, maybe I could lend you a hand some time?"

"..."

"Shit, wait, that didn't come out right." He looked away, panicked, blushing furiously. "I mean, not that I wouldn't, but like, wow, that was way too forward. I just meant I could give you a massage or some stronger tea or something." His gaze slowly, cautiously returned to Gaster, who stared at him, agape.

"Did you just..."

"No, of course not!" Sans spat out, a bit too loudly. He laughed nervously. "It's not like you'd be interested... right?"

Gaster sighed, sitting back in his chair.

"Wow, I'm sorry, sir. I mean, I like you, but I wasn't planning on letting you know that, because that would be weird. I really do admire you, and your writing! And I've always dreamed of working under you, but then, I actually met you and, well..."

"And now you'd like to play under me, too?"

"Ffff-"

"Sans," he said, solemnly, "Let me give you some advice? Don't flirt with your boss. For that matter, don't flirt with anyone who completely outranks you. I've been where you are, and it didn't end well. It's inappropriate, unprofessional, and it puts you at risk, not to mention it can look bad on the person above you."

"Wait, you had a thing for Marlick???"

"Wh- No!!" Gaster hissed. "God, no!! Ugh, just thinking about that old fool makes me want to retch! No, I- no. Anyways, What I mean to say is that I can't be fooling around with an employee, especially one so young. You're right around Alphys's age, for goodness sake! I'm old enough to be your father."

"Yeah, I know." Sans said, feeling his blush return. "Look, it's just a silly crush, I'll get over it. But if there's any other way I can help you, or if you want me out of the lab, just let me know. I really don't want to stress you out more than you already are, I mean it."

"You're fine, Sans. Thank you. This isn't where I thought today would be headed, but that's okay. Why don't we take this to go, and get back to the lab?"

"Sure."

* * *

 

Gaster realized too late that he could have lingered in the upper lab, not gotten on the elevator with Sans, and avoided the long and awkward ride down. The air between them was smotheringly tense, both of them silent, both probably aware that small talk would just make things worse. He glanced down at Sans from the corner of his eye. The young skeleton was looking away, eyes fixed onto a point on the wall next to him, probably looking right through it.

He still couldn't believe Sans had come onto him. He felt bad for his reaction, but he really hadn't seen it coming. _I'll have to make sure I don't do anything to lead him on in the coming weeks_ , he thought. Then, _Oh no, have I been leading him on?_ He certainly didn't think so, but anything could be misconstrued... Perhaps he'd been too casual with physical contact? That was something he'd have to avoid in the future. _What a shame._

It was an absolute relief when the elevator came to a stop and they were able to leave. 

**Notes for the Chapter:**

> Yeah, I think that's a good stopping point :-)
> 
>  
> 
> Boy, I am sooooo excited for the hand-jive, you have no idea lol.


	13. The future is tense

**Notes for the Chapter:**

> :-3 Okay, Pornpyrus made some really cute pixel gifs of Wickett and Juneborg, and I'm dyin'.
> 
> http://pornpyrus.tumblr.com/post/138969488851/rly-quick-lil-pixels-i-rly-like-pepperchans
> 
> Sorry for the long wait between this chapter and the last one.   
> Murphy's Law states that whatever can go wrong, WILL go wrong, and that's the law I live by.

Hours later, Gaster was still processing what Sans's little confession. His attention span was suffering greatly, and it was becoming more difficult to keep focused on any one thing.

Whenever Sans's back was turned, Gaster would find himself staring, really _looking_ at him, taking him in. He had never really considered it before, (why would he?) But Sans certainly wasn't unattracive. Short, round, bony? Sure. A bit outside of Gaster's usual tastes, but all in all, he was good looking. And he wasn't bad company, either, if their limited interaction was anything to go by. If circumstances had been different, perhaps...

But circumstances weren't different. He couldn't afford to be entertaining that thought. Besides, he didn't really have time to be fussing over someone, maintaining a relationship.

Sans wasn't offering a relationship.

That... was almost worse somehow.

He turned his attention back to the task at hand: the power supply unit for the cannon. He had it hooked up and was running a small current through it to test the emergency shutoff. It was functioning fine, there really wasn't much to do there. He was waiting for his team to finish assembling the cannon, and then he would connect the two. He drummed his fingers on the box, and looked over to where Juneborg and Sans were working, attaching the reflectors to the inside of the barrel. They both looked so focused. Gaster's gaze ran up the young skeleton slowly before settling on his collar, where a thread had come loose. Maybe it was time to invest in better-quality labcoats.

He looked up at Sans's face, only to find Sans staring back. Gaster tensed, embarrassed, and raised a hand to his own collar, pointing at it. Sans squinted first at Gaster's collar, then with a glint of realization, looked down at his own and spotted the thread. He laughed softly, then sheepishly tugged it free and stuffed it in his pocket. He looked back up at the doctor with a shrug. Gaster shook his head and returned to work.

For a few minutes, anyway. The next time Sans turned away, Gaster's attention was on him again.

He wasn't sure when he had drifted off, but when he awoke he was alone in the lower lab, still seated at his desk, a slip of paper tucked under his arm. He picked it up and looked it over, rubbing the sleep from his eyes. It was a hand-written note from Sans, explaining that the crew left a bit early, so as not to disturb him wile he slept.

He held the note there in front of his face for a moment, tracing over the lettering with his eyes. Sans's hand writing was small, round, and looked much like Sans himself. The doctor imagined him sneaking up and slipping the paper under him, and felt just a little warm in the cheeks, an unwelcome feeling. He set the paper back down where he'd found it, stood up and walked over to the cannon to check up on what progress his team had made. The internal structure looked to be complete, but the shell still needed to be attached to itself. Regardless, it was complete enough that he could begin to hook up the power supply, so he set to work.

If they kept up at the pace they were going, the cannon could be finished by the end of the next day, and they could run their test fire Friday morning. If not, there was always the weekend. As long as everything was completed by Monday, they were golden.

As he worked, he could feel another migraine building. He tried to ignore this one, pouring his concentration into the job in front of him. When it finally became too much to bear, he set down his tools, and made his way to the upper lab. _Learn from your mistakes_ , he thought, _I did promise it wouldn't happen again_. He made himself a cup of the tea Sans had given him, brought it up to his desk at the office, and just sat there, sipping it slowly. The tea dulled the edges of his pain, and he could think again, at least. He drifted back to sleep.

* * *

 

Very quietly, Sans removed the empty mug from the doctor's desk, and replaced it with a fresh cup of coffee. Gaster's eyes opened slowly, blinking, and looked up at Sans, but the doctor said nothing, didn't move his head, only closed them again. Sans sighed, relieved, and turned away.

"Thank you," he heard Gaster whisper.

It sent a jolt right through him.

There was a palpable tension between the two of them throughout the day. Sans could feel it in their few verbal exchanges, brief and to the point. He could feel it in the distance between them, which never seemed to be enough. If he and Gaster had to stand next to each other for any reason, one of them would take a step to the side, a polite gesture to create space. He kept his head down to avoid looking the doctor in the face.

But every now and then, he could feel Gaster staring at him.

* * *

 

Gaster materialized an extra set of hands to hold the last pieces of the shell in place while Juneborg fastened and welded it together. Sans and Wickett stood back by the door, arguing about some application of magic. Larkeet was hunched over one of the computers with Alphys, explaining the tuning program. After this, the cannon could be considered finished. Or, it was built, at least. It still needed to be calibrated, but it was definitely a complete thing.

There was still just enough time in the day to power it up, and make sure everything was in order. They could spend the next day preparing for the first test fire, and then recalibrating everything before firing it again, because Murphy's Law was most applicable when the pressure was on.

At least everything was going well so far. Though the day had been a bit tense, and Gaster couldn't really focus on anything completely because he was expending so much energy keeping an eye on Sans, and trying with all his might to catch himself before he did anything to lead the young man on. His head was pounding. This wasn't fair.

Not fair that the pain was the worst when there was a deadline to meet. Not fair that the headaches would come back not long after their presentation. Not fair that he had a reputation to protect. Not fair that he would have to walk on eggshells around Sans. Not fair that the sound of the welding torch was now driving him up a wall. Not fair that he just couldn't relax lately.

He wanted so badly to relax.

And he had been offered help, been offered a chance to relax, and it was tempting. He didn't even really know what Sans was offering, (a massage? hypno-therapy?) but if it really helped, and Gaster could focus just long enough to get through their presentation, wouldn't that be worth it? Worth whatever consequences he might face?

Juneborg pulled the torch away and turned it off. That was it, the shell was complete. Everyone that had been standing around the edge of the room gave a big woop, and Gaster flinched at the noise before putting on a big smile. They were all looking to him for the next step. He walked over to his computer and booted up a command program he had written to control the cannon. He began the countdown at ten, and everyone counted with him.

On the count of zero, he turned it on. A dreadful humming filled the air, and Juneborg pulled back further from the cannon as the eyes on the top of the shell lit up. Gaster could hear the inner components react as the electricity reached them, and something in the back of the jaw clicked.

Then the humming dropped in pitch, and eventually stopped. Something had gone wrong. Gaster sighed and brought a his hand to his face. Alphys was the one to step forward and look the machine over, inspecting it for a sign as to what had failed.

"Um, Gaster?" she called, motioning him over.

"What is it? he groaned. Everyone was watching the cannon nervously now.

She waved him over again. "There are, I think, teeth marks all over the power supply and its cord?"

He jolted upright and bounded over. Oh god, she was right. A cluster of tiny bite marks littered the end of the cord where it connected to the power supply box, as well as the box itself. Gaster was furious. He detached the cord from both the box and the wall, and threw it on the ground. Alphys backed away as he turned around. Everyone in the room looked concerned. He took a deep breath to calm himself, as the pain in his head began to cloud his vision.

"A minor setback," he assured them, "I'll replace this cord and repair the box tomorrow morning, and if we don't get this thing up and running by tomorrow, I'll fix it myself over the weekend. Why don't we all wrap up for the day and head home? I could sure use a good night's rest." He smiled, fake, calm, cheerful. This was agony.

There was a murmur of agreement among them, and everyone began to disperse. He watched as Sans turned slowly away, walking down the corridor and chatting with Alphys. There was a fluttering, a squeezing in his chest. Not as strong as the squeezing in his head, but noticeable.

Damn the consequences. It was time to ask for help.

* * *

 

It took everyone a while to leave the lab. They were all chatting, both worried and excited for the next day. Sans almost left with them, but remembered his daily report when he was halfway out the door. With a "Catch you later!" to Alphys, he headed back to his desk. He had barely begun when he heard footsteps on the stairs behind him.

"Sans?" Gaster called out softly.

"Yes, boss?" Sans replied. He kept on typing, kept his attention on the screen in front of him.

"Is... Is your offer still standing?" the doctor asked, barely above a whisper.

He turned suddenly in his chair. The question sounded like the setup to a bad joke, but Gaster looked like an absolute mess, a quivering mess that was breathing too heavily and couldn't keep its eyes open. Sans's pulse raced. "Are you okay?" he asked.

"No, I'm fine. I'm a bundle of stress, and frustration, and pain, but I'm fine. Can you help me?"

"I- yeah, sure. What do you need?"

"Whatever you had in mind yesterday, I don't care."

"Okay, yeah." He stood up slowly and brushed himself off. "Um, we've got a few options here, I think I have some painkillers that might help, or-"

Gaster took a step towards him.

"H-here?" he asked cautiously "D'you wanna do this here?" His face was hot enough to fry an egg.

"No," said the doctor, "let's go back to my house. I might as well use it for something."

* * *

  
Gaster felt almost immediately better having stepped out of the lab. Getting away from those damn florescent lights was probably half of the reason, fresh air the other half.

His house wasn't terribly far from the lab, but it felt like forever before they arrived. Sans trailed a couple of steps behind him. He made a few attempts at small talk that fell short and lapsed back into silence.

When they arrived outside the gate of the small building, Sans pointed out the overflowing mailbox and turned to Gaster with a questioning expression. The doctor sighed. Had he known he was going to be returning home with company, he would have dropped by earlier and tidied up. Now, Sans was going to be subject to his embarassment of a house, unkempt and unused. Hopefully he wouldn't be too judgemental. This was unplanned, after all.

It took him a nervous minute to find his housekey among the dozen others on his keyring, but Sans waited patiently, leaning up against the house. Finally with one swift motion, he unlocked the door and swung it open. "Please ignore the mess." he whispered.

"Don't worry," Sans said, shrugging, " 's not why I'm here."

Gaster motioned Sans in first, and followed him through the door, locking it behind them.

**Notes for the Chapter:**

> Okay, soooo, the 'Hand-Jive' (~*saucy*~) is coming up next chapter, so for those of you who'd rather avoid an explicit sex scene, just go ahead and skip it, and I'll put a recap of anything important. (plot-related) at the start of the following chapter.
> 
> Thanks again to all of you who read this! You're all really kind and supportive (and patient!), and I love you! :'-3


	14. Hand-Jive

**Notes for the Chapter:**

> WE ARE NOW ENTERING THE BONE ZONE, PLEASE PROCEED WITH CAUTION.  
> If you're not into smut, you can skip this chapter entirely, I will make note of any details that are plot-relevant and put them in the notes at the start of the next chapter... which should pick up about 60 seconds after this one ends.

"Take off your shoes, please." said Gaster, Pulling the door shut behind him, "Your Jacket, too if you like. You can hang it up by the door." He turned a dial on the wall and the lights overhead flickered on dimly.

Sans looked around silently as he shrugged off his jacket and kicked off his shoes, waiting for Gaster to do the same. The living room was surprisingly clean, cluttered but organised, with the odd stack of papers or bits of machinery lying about. There was a piano nested up against the back wall.

"I didn't know you played the piano," Sans said curiously.

Gaster rose slowly. "It's been a while," he replied, smirking, "but rest assured, I know a thing or two about tickling the ivories." He chuckled at San's furious blushing and stepped forward. "Come along, my bedroom is this way."

Sans followed him down a short hallway. "Wow, I'm used to the couch being a first date kind of thing. You sure you wanna go straight to the bedroom?"

The doctor stopped at a closed door, turned to Sans, and frowned slightly. "This isn't a date, Sans," he whispered.

"Oh, heh. I know." Sans shrugged as his guts twisted. "I don't know what else to call it, sorry."

"Don't call it anything, this should stay between us."

"Yeah, okay." he whispered. His heart sank.

Gaster opened the door and turned the lights on, low. Sans followed him in, watching him closely as he unbuttoned his shirt with deft fingers. "You can undress," he said. He pulled the shirt off and tossed it aside.

"Can I leave my undershirt on?" Sans asked nervously. _Casual encounter means clothes stay on. Less intimate that way._

"Certainly," Gaster said, reaching for his belt buckle. He slid the belt right out of the loops, eyed it for a moment, then tossed it aside and began unfastening his trousers.

Sans pulled off his pants and watched the doctor sit down on the bed, in nothing but underpants, waiting for him. He was so nervous, he could hardly breathe.

"Are you going to join me?" he asked. "This... isn't your first time, is it?"

"Hah, no," Sans said, hooking his thumbs under the waistband of his own boxer shorts. He'd certainy gotten around in his college days, but he wasn't going to tell Gaster that. "I've got some experience under my belt." he assured him with a wink.

"We'll see." Gaster replied, tuggging Sans forward by the hem of his shirt, onto his lap. He had his arms wrapped around Sans, pulling him close, and leaned in to kiss him just under his mouth. The skeleton's hands moved their way down to Gaster's hips, fingers rubbing circles into the soft flesh. Gaster was tense, shivering, as he pulled back from the kiss.

"Hey," Sans whispered, tapping his forehead against Gaster's cheek, "mind if I move behind you real quick?"

"...Alright."

Sans pushed himself up and crawled behind Gaster, seating himself right at the doctor's back. He had come here for a reason, and by golly, he was going to fufill his purpose. He reached up and began to rub the doctor's back, starting at the nape of the neck and moving downwards in gentle spirals. "Okay, let's get you relaxed," he said. He took the chance to admire Gaster's body from this angle, a strong skeletal structure coated in soft, malleable skin, white and gray, with black patches that mimicked the hollows that Sans had between his own bones. A mimick of a mimick. Cool.

He really liked the way the spinal column protruded slightly, a bunch of little bumps that he ran his thumb down. Gaster tilted his head back and hummed softly at this, his posture was more relaxed, his breathing drawn out and heavy as Sans rubbed him down. Mission accomplished, on to phase two. He leaned up and forward, resting his chin on Gaster's shoulder. "Hey, Gaster?" he whispered. "Don't suppose you like being bitten?"

Gaster took a moment to answer. "I suppose it depends on the dentition." Another pause. "Gently, please."

Sans nodded and parted his teeth, placing them right at the juncture between Gaster's neck and shoulder. He pressed his teeth into the flesh slowly, gently, swirling his tongue over the surface and exhaling. He reveled in the moan Gaster just barely held back, in the way his breath stuttered. He released that part of Gaster's neck and moved to another, nibbling and licking the doctor's skin tenderly. He ran his hands over Gaster's ribcage, palms pushing forward and fingers dragging back towards the spine until his breath was ragged.

Gaster pulled away long enough to turn himself around, then leaned over Sans and pushed him onto his back. Their mouths joined and Gaster slid his tongue into Sans's mouth, over the tip of his teeth. San's could feel the doctor's erection pushing up agains his pubis, through his boxers. Gaster pulled back, panting.

"Should I try biting you as well?" he asked.

"If you want to, I'm not going to stop you." Sans shrugged and turned his head to the side. Gaster leaned down and nibbled gently on the collarbone that was presented to him, and Sans had to fight to hold in his laughter as the blunt teeth clacked uselessly against his bones. _Ahh that tickles, wow fuck why?_

"Okay, thif ifn't working" Gaster mumbled, his mouth still wrapped around the bone. Sans laughed, then moaned as Gaster began to suck on his clavicle..

"Ohhhhh, fuck yeah." That was the ticket. His hips bucked forward a bit and Gaster ground into him, pushing his hips down back into the bed.

"Alright, that's enough foreplay. Let's stop teasing, hm?" Gaster mumbled. He reached for Sans's boxers and pulled them down halfway. "Hmm? No genitals?" he asked, looking down at the bare pelvic bone that was now in his view. He ran his thumbs along the upper edges.

"They're uh, made to order," Sans gasped, "what do you fancy?"

The doctor leaned in and kissed the side of his head tenderly. "Surprise me," he whispered.

Sans shivered, excited. He had to think fast. Stalling for time, he reached down and pushed his boxers the rest of the way off. Next, he went for Gaster's waistband, but his hands were pushed away, and Gaster slowly pulled off his own shorts, now completely naked, and Sans could hardly stop his eyes from roaming over the Doctor's body, looking over every inch of him and his (now visible and _very_ erect) cock.

But when he did look up, Gaster was staring at him in the dim light, smiling. He closed his eyes as the doctor reached up to stroke his jaw, took a deep breath, and focused his magic, allowing it to gather inside his pelvis. Mimicking what he had seen of Gaster's magic earlier that day, he formed a thick disk, with five long protrusions aligned next to each other on the edge. He opened his eyes and smiled back at Gaster.

"How about a hand job?" he asked casually.

"Oh my goodness, Sans." Gaster groaned looking down at the magical formation. He had to sit up to cover his mouth; laughter still escaped between his fingers. "I hope you know what you're doing." He said dryly.

"Yeah, I got this, come on."

Gaster maneuvered his cock to the hollow of Sans's pelvis, where the new-formed hand wrapped around it, giving it a brief squeeze that made him whine and buck forward. Sans wrapped his arms around Gaster's chest, gripped onto his back tightly as the doctor began to move with a more even rhythm, pushing himself in and out of Sans's tight grasp.

Sans watched Gaster's shoulders, his arms, and the muscles in them, even without much definition, he could see them straining and flexing to hold up his body.

"D'you want me on top?" he asked gruffly. Oh, being fucked like this was doing funny things to his voice.

"Not if you're fine with laying down." Gaster replied after a moment of consideration. "Wait, actually."

He sat back, upright, and pulled Sans up onto his lap, thrusting upwards, with the skeleton's bony legs wrapped around his hips, arms around his waist. He leaned in for another deep kiss, and Sans's tongue met his own eagerly. His hips stilled as his focus shifted to their mouths, and Sans took advantage of the opportunity to slide his magic hand up and down Gaster's shaft in slow strokes.

"Mmnnnff!" he moaned into Sans's mouth, pushing his hips up and into the motion. He pulled back from the kiss to catch his breath with saliva still on his lips, tongue sticking out just past his teeth. Sans rested his forehead against Gaster's sternum, loosened his grip on the dick slightly, and began to stroke faster, urged on when Gaster wheezed and grabbed his femurs, tightly.

He could feel how close Gaster was in the way his breathing deepened, the way his member went absolutely rigid, and his hips bucked up wildy. With a few rough strokes, he sent Gaster over the edge, and looked up to watch him come, chest heaving and eyes closed tight. Hot strands of cum shot up from between his fingers, pelting the inside of his ribs and sliding down in a way that made Sans dizzy with pleasure. He gave the still twitching cock a tight squeeze, and the doctor tilted his head back and made a keening sound.

Gaster reached up and gripped the front of Sans's shirt to pull him in for a series of slow, shallow kisses on his mouth, and Sans made little 'tsk' noises with his tongue on the back of his teeth to show his appreciation. Finally, he let his magic dissipate, and Gaster's cock dropped against the back of his pelvis with a gentle 'thunk' that made them both jump.

"Thank you... so much," said Gaster, "I-that, oh god I feel so good right now, thank you."

"Heh, any time." Sans chuckled lowly "How's your head feeling?"

"Hhhnnnn."

"Glad to hear it." He dismounted the doctor carefully and flopped onto the bed on his back, watching Gaster watch him with half-lidded eyes, smiling.

"I am parched, and exhausted," Gaster announced in a whisper, "Would you like something to drink?" He reached out and stroked Sans's arm with his palm.

"I'm good, thanks," said Sans.

"Yes... you are." Gaster said with a smirk as he got up from the bed and shuffled out of the room.

**Notes for the Chapter:**

> Heh.


	15. The Aftergl- ...Oh.

**Notes for the Chapter:**

> Things you may have missed if you skipped the last chapter:  
> -Gaster has a piano, as well as an overflowing mailbox.  
> -Lights in his home are controlled by dimmer switches.  
> -This chapter begins approximately sixty seconds after the last one ends.

Within seconds, Sans felt sleep overtaking him. His eyes had only closed for a moment before Gaster was back in the room, turning the overhead light up slowly. "Falling asleep already?" the doctor asked, teasing.

Sans sat up quickly, forcing his eyes open. "Nope!" he insisted, scooting off the bed. His cheeks were hot, pulse racing. _Fuck, I've got to get out of here_ , he thought. Being half-naked in the light made him feel self conscious. He stood up shakily and grabbed his clothes off the floor, throwing them on quickly.

"Are you leaving?" Gaster asked. He was leaning up against the wall by the door with a glass of water in one hand, still naked, still very relaxed. _At least I did what I came here for_ , Sans thought.

"Yeah, I'm a mess, I should go home," He replied. He tried to put his pants on upside down, realized his mistake, then flipped them over and pulled them on.

"You can use my shower, if you'd like. You don't have to go."

"Thanks, but I really should be heading out." He straightened his clothes. Sweat and other things were beginning to dry on his bones, and he felt absolutely disgusting. A shower sounded nice, but he could do that at home. "Just have a good night, and get some rest, and I'll see you at work, yeah?" He was halfway out the bedroom door when Gaster grabbed his shoulder, halting him.

"Sans, thank you. For all of this. I know I chastised you for flirting with me, but I'm grateful for your help, truly."

He looked up at Gaster's face, could see the sincerity there, looked away. "Hey, any time," He croaked. "And don't worry, I won't tell a soul, ok?"

Gaster nodded and released him. He pulled on his jacket and shoes, and left the house without looking back.

 

* * *

 

Gaster sat down on the edge of his bed, ready to collapse any second. His head was buzzing, pleasantly for once. He looked around his bedroom, empty. He _felt_  a bit empty. He laid down on his belly, wishing Sans had stayed to rest there. He couldn't blame the poor boy for wanting to leave, but he didn't want to sleep alone.

 _Maybe next time, if there is a next time, I'll convince him to stay_ , he thought, as he drifted off.

 

* * *

 

Sans threw himself face down on his bed the moment he got home, not bothering to undress. He wanted to scream.

He was terrified of the doctor kicking him out, so had saved him the trouble, but in doing so, had probably missed his only damn chance to spend the night there, next to him. _Add that onto the pile of mistakes I've made this week_ , he thought.

All of it. All of it had been a mistake. "I slept with my boss," he mumbled into his pillow. "He warned me not to, but I just couldn't say no, could I?" He had self respect, buried somewhere. He could have refused. But he didn't, because he was so desparate. And now Gaster knew what a fool he was.

He woke up the next morning and thought about calling in sick, taking the day to recooperate from his idiocy. But that wouldn't do. They were probably going to be testing the cannon, and he wanted to be there. He showered, got dressed, and hurried to work.

"Hey, Sans, you ok?" asked Juneborg at the top of the stairs. She was early. Wickett was there, too. Looks like they were all excited to get this done.

He shrugged. "Yeah, I'm fine." _I'm an idiot, though_ , he wanted to add.

"You look like hell. Tired?"

"Eh, couldn't sleep."

"Heh, me neither. I stayed up late watching some documentary on cockroaches."

He nodded and sat down at his desk, bringing up the feed from the oscilloscope. He narrowed his eyes at the screen. The feed had been interrupted. The diagnostic tab was blinking red. He clicked over to it. "Aw, fuck," he sighed. "I gotta go down to the barrier and check the scope. See you guys later."

There wasn't anything wrong with the scope itself, it was the little network box that had lost connection. Sans spent a few minutes fiddling with it, trying to recall what Alphys had told him to do to reset it. He flipped the switch, pressed the button, realized he had gotten the order wrong, then held the button and pressed the switch. The little lights on the box changed from yellow to green. Success.

He double checked that everything else in the area was in order, then headed back to the lab. What a great start to the day. Upon entering the lab he made a beeline for the elevator, reaching into his pants pocket for his key card. Nothing. He checked the other pocket. Empty. It wasn't in his labcoat pockets, either. Had he left it at home? He was frisking himself when he heard footsteps behind him, and saw Gaster's arm reach forward to swipe a card against the reader.

"I thought I told you **not** to lose this." The doctor said, handing him the lanyard and card.

Sans looked down at the card with his name on it, then up at the doctor's smirking face. "I... I'm sorry. How did..."

Gaster leaned close to him. "You left it at my house," he whispered. Sans looked away, blushing as Gaster pulled his own card from his pocket, then scanned it as well. The elevator dinged.

"it must have fallen out of my pocket, sorry."

"You're fine." the doctor said, stepping into the elevator. Sans followed him in. "Just don't make a habit of it."

"Leaving it at your place?"

"O-or at anyone's." Gaster looked up to the ceiling so Sans couldn't see his face. For a while, they were both quiet.

"You look pretty good today. At least, you don't look so tired."

"Thanks to you. I got the best night's sleep I've had in weeks."

Sans allowed himself to smile. "Glad I could help."

They rode the rest of the way down in silence.

 

* * *

 

With the click of a button, Gaster turned on the cannon. It buzzed with energy once again, this time not halting and powering down. A collective sigh of relief swept through the room, followed by a muffled Gasp from Juneborg as the blaster's eyes lit up.

"Alright, it looks like we've got a stable current going," Gaster said, "if everyone will don their protective equipment and stand in one of the areas Sans has taped off, we'll try getting it to fire.

With safety goggles and hearing protection in place, everyone spread out through the room, standing in the areas marked 'safe' on the floor. Gaster typed a command into the computer, and the machine began to thrum with a cold, heavy energy that filled the air around them. Gaster flicked his wrist upwards, and the cannon's jaw opened wide, exposing a bright blue orb of energy in front of the firing mechanism.

"Larkeet, the count down please." Gaster commanded.

She counted down from five. As the energy built inside the cannon, so did the tension in the room. Hopefully this would go smoothly, and their hard work wouldn't be for nothing Gaster held his breath.

"...One, Zero!" she called out. Gaster immediately tapped the button to fire.

The blast was intensely bright, even with protective eyewear, Gaster had a hard time looking directly at the cerulean beam of magic that was erupting from the cannon's maw, instead focusing on its target, the pitch tarp on the opposite wall. At the collision point, tiny blue swirls of flame and spark danced around on the surface of the fabric before being absorbed by the fabric's enchantment. The air in the room felt more dense, the scent of ozone flooding them.

Six seconds in, he hit the kill switch, and the cannon ceased, jaw closing. He glanced around at his crew, incredulous and awestruck at the powerful thing they just witnessed, that they had helped create. How immensely satisfying to see it in action.

After everything was shut down and unhooked, the crew chatted eagerly about their plans for the coming days.

"You're not stayin' the weekend again, are you, Gaster?" Larkeet asked, "I mean other than dog-proofing the lab, I'd say we're pretty much set for Tuesday."

"I'd like to run a few more test fires," Gaster assured her, "Gather some actual information about the effects of the beam, since this one was just to make sure it actually works. But we can do that on Monday. There's no way I'm firing it alone, you never know what could go wrong."

"I can think of a a few things! Kaboom, you know?" She laughed.

"Yes, exactly. But no, I think I'll keep the lab closed this weekend. I have some things to do at home..." He glanced over at Sans, who was talking excitedly with Wickett. The lights in the skeleton's eyes flickered over to Gaster momentarily, then away. "I really should clean my house, empty my mailbox, that sort of thing."

"What, you mean you don't live here?!" She gasped mockingly, "You could have fooled me!"

"Yes, ha-ha, that never gets old." He rolled his eyes at her, waving her off. "What are you doing this weekend, anyway?"

"Hockey game! Wanna come watch? We're gonna kick Snowdin's butts."

"I don't see how you could beat a team that _lives_ on ice, but I'll consider going. It should be interesting, at least."

"You're damn right, it will be!" She watched his gaze drift back over to Sans. "I'd understand if you're busy though, that new hobby of yours must be pretty demanding."

"What hobby?" he asked, still looking away.

"Osteology."

Gaster whipped his head around to look at her, eyes narrowed. "Excuse me?!" He whispered.

"I'm just sayin'..." she shrugged.

He stepped closer to her. "What are you talking about?" he demanded.

"I mean you've been staring at Sans an awful lot these past few days, it doesn't take a genius to figure out what's going on," she whispered, winking at him. "Don't worry, doc, I won't tell him. Your secret's safe with me."

"There is nothing to tell!" He was blushing for sure, giving himself away.

"Mhm, sure. Come to my game, ok?" She turned from him, feigning sudden interest in a lop-sided stack of papers.

He watched silently as Sans, Wickett and Juneborg shuffled out of the room, thankful for their obliviousness to the conversation he was having.

"Blackmail won't work on m-"

"Sure it won't, but you're coming to my game anyway, right?"

He crossed his arms in response, silent.

"I think it's kind of cute, you know," she chirped.

"You don't think it's... wildly inappropriate? "

"You're asking the wrong bird on that one," she replied, shuffling the papers about. "Remember, my husband's eighteen years older than me, and his ex wife was twenty-six years older than him. And she was his doctor. I don't really have a leg to stand on, judging you. I do think..." She folded her arms and leaned against the table behind her. "...that you got really lucky last time. I mean, I know things didn't work out, but they could've been a lot worse. I guess you just have a lot to think about before you decide whether you want to pursue something with him."

He stared down at his feet, his guilt obvious. "Well, it might be a bit late for that..."

 

* * *

 

Up in the office, Sans was typing up his daily report, while Juneborg and Wickett discussed possible ways of disassembling the cannon once the time came to move it.

His phone buzzed from his pocket, and he pulled it out to find a text from his brother, asking whether he was coming over for dinner again this weekend.

After a moment of consideration, he typed out an affirmative response, thankful he'd have something to do. _I really need a hobby_ , he thought, _something that isn't embarrassing myself_.

He and his coworkers were oblivious to the shouting match that was currently taking place in the lower lab, Larkeet's angry cries of "REALLY, GASTER?! **REALLY**????" never reaching their ears.

**Notes for the Chapter:**

> I figured it was about time someone yelled at him. Shrug.


	16. It could have been a fig, but it wasn't

**Notes for the Chapter:**

> Author's headcanons, ho!!!

Sans was the last person left in the upper lab after everyone else had gone home. He had just made it down the stairs to the lobby when he heard the elevator ding and Dr. Gaster and Dr. Larkeet stepped out.

"...so I don't forget. And it's the west rink, correct?"

"That's right! Make sure you bring a sign to cheer for me, so I know you showed up."

"I will not." Gaster huffed.

Larkeet laughed. "Oh, hey **Sans**! You still here?" She chirped, making her way over to the skeleton.

"Ah, yeah, I was just heading out." He shrugged.

"Ooh, me too! Have a good weekend, and good luck, okay?" She grinned brightly and layed a wing on Sans's shouler, then turned to Gaster with a scowl. "Eight o'clock, Sunday, west rink, don't forget!" And before Gaster could respond, she was gone in a flurry of feathers.

Sans looked over to Gaster, bewildered.

"I'm supposed to go watch her play hockey." The doctor said helplessly.

"Ah, that makes sense." mumbled Sans.

They fell into silence, with Sans's eyes flicking up between Gaster's face and the floor, and Gaster just staring. Sans felt too stiff, his breathing tight. He wasn't sure what to say, or if he should say _anything_. It sure would be easier to just let the doctor set the pace of this conversation, if it was going to happen, so that Sans didn't overstep and embarass himself again. Or they could just not bring anything up about the previous night, let it fall back and become something both of them remember, but neither ever speaks about. It wasn't a big deal, even, just a favor. Nothing intimate.

His gut twisted a little. He wanted to talk about it, even if there was no discussion to be had.

Finally, Gaster broke the silence. "Well!" he said, making Sans jump a little, "Any plans for the weekend?"

"Oh, um... Just dinner with my family." That was boring. "Might go to the library in New Home, see if there's anything new." He shrugged. "How about you? Hockey game, right?"

"Yes, that's right." said Gaster, " Perhaps I'll get some cleaning done, too. My house isn't quite presentable, at the moment." He clasped his hands together.

"Heh. Yeah, I... yeah." Sans mumbled, looking down. After a few more moments of silence, he spoke again. "So, I should get heading home. Have a good weekend, Doctor"

"Wait," Gaster called to him, "Are you f-free tonight?"

"I... yes?"

"I was wondering if you'd care to join me." He said, straightening his back. His face was tense, Sans could tell he was struggling to act calm and composed.

"I'd love to," said Sans.

"Wonderful! Just, wait for me outside, I have something to take care of before I lock up."

"Alright." Sans hung up his lab coat, then walked out the door and leaned against the wall just outside. Well, he hadn't given that any thought before agreeing, had he? _Pathetic_. He slumped a little. _At least it's a good sign that he doesn't have a raging migraine today, right?_

He stood up straight when Gaster came out, and silently watched him lock the door.

"So," said Gaster, "What are you in the mood for?"

"Anything you want," Sans said lowly. _Fuck, that was too pliant, too eager,_ he thought.

The doctor blushed. "I mean to eat, Sans." he said, flustered. "I'd like to take you to dinner."

"Oh." Sans looked down, grimacing. "Sorry, I thought... You know what? Same answer. I'm up for anything."

Gaster folded his arms in thought. "Alright, I know somewhere nearby. Follow me."

The doctor led him to a small diner tucked away in the corner of Hotland, with a bright, friendly interior. There were plenty of seats open, despite the fact that it was still fairly early in the evening.   
  
They got a booth in the back of the diner, in the corner, and had only just sat down when Gaster began to speak.

"I believe I owe you an apology," he said, "for my treatment of you the other day, as well as everything that came afterword. I was tired and upset and paranoid, and I shut you down in a way that was rather rude. I'm sorry."

"It's fine," said Sans. "I can understand where you were coming from. I just don't get what made you change your mind." He looked over the menu while Gaster mulled over what to say.

The doctor was fidgeting with his fingers. "I suppose I had never even considered the possiblity of... of being with you... until you brought it up. And once I started thinking about it, it didn't sound like... well, no, it still sounded like a bad idea, but maybe a little less so than I had first thought. Like I said, I've been in this situation before, but from your position."

The waiter came by to take their orders. "Oh, Um, Sans? You first. Get whatever you like, it'll be my treat."

Sans thanked him ordered a plate of pancakes and a soda, to Gaster's amusement, while the doctor chose a plate of pasta and coffee.

"So," Sans began once the waiter had stepped away, "You like the thought of being with me? But you still think it's kind of a bad idea."

"That doesn't come out very nicely, does it? I'm sorry."

"No, but I did give it some thought, and I can see where it could go wrong." He shrugged into himself. "If anyone else in the lab found out, they might not like it. And the amount of power you've got over me and my career would be pretty easy to abuse. All that said... I don't know, Doc. I mean this all started out as a silly crush, and I never meant to let it slip. I definitely didn't ever expect you to return my, um, feelings." He looked away as the waiter approached and set their drinks on the table.

"Well, I think I do." said Gaster once they were alone again. "Now what?"

"What do you want?" Sans asked.

Gaster rubbed the side of his forehead. "I don't know," he admitted, "I don't know all that much about you, but I enjoy talking to you, I enjoyed spending time with you last night, too. I wouldn't mind doing that again." He blushed just slightly.

Sans chuckled. "Well, the next time you have a headache, let me know."

"With or without a headache, if we sleep together, I'd be happy if you spent the night."

"Oh, yeah, I left in kind of a hurry, didn't I?" He winced "Sorry. I figured you'd have wanted me out so you could rest. And maybe I was a bit embarrassed about being seen like that. Just kind of _em-bare-assed_ in general." He grinned as he let the joke sink in.

Gaster snickered. "You literally have nothing to be _ass-shamed_ of though, Sans." He said, right on cue.

They were still recovering from a fit of laughter at those terrible jokes when the waiter arrived again with their food, baffled.

"Thank you," said Gaster, wiping a tear from his eye. The waiter nodded and walked quickly away. "That reminds me, is it 'Comic Sans' that you were named after?"

"You could say that," Sans said as he regained his breath. "It's not actually part of my name, but that was what my mom was going for, I think." He picked up his fork. "How did you know?"

"It's a very old skeleton tradition, I know that much. Nice to see that it's still going. Your brother too, then? And your father?"

"Papyrus, yes, and my mother, actually. One of them. Her name's Verdana."

Gaster froze with a forkful of pasta inches from his mouth. "Verdana Calibri? Really?"

"You know her?"

"Well, she's a news anchor, everyone does. Besides that, I went to school with her. She _hates_ me." He sat back. "If she knew we were dating, she'd have me ground into dust."

Sans leaned forward. "Are we dating?" he asked, tentatively.

"Well, this is a date." He shoved the now-cold forkful of pasta into his mouth, chewing thoughtfully.

"I didn't want to assume. What did you do to piss her off, anyway?"

"It's a long story. A very long story. I won't go into it, but if you ask her, I can assure you half of what she'll say about me is a lie."

Laughing, Sans poured a flavored syrup over his pancakes, then took a bite. They were light, fluffy and flavorful, not like the ones his mother made. He sighed contentedly. "So, since this is a date," he said after finishing his bite, "May I ask what your first name is? I've only ever seen it written as 'W.D.' and everyone calls you 'Gaster', or 'Dr. Gaster', even Alphys."

"You may not ask." Gaster decided after a moment of consideration. "My first name is like your last name, just a formality. And I never respond to it. I can tell you that I was named after my grandfather, who was a skeleton, and that's all."

"Fair enough. What about the rest of your family? Do you have any siblings?"

"I have one, a brother named Web. I don't know if he's still around though, I haven't heard from him in years. He was already an adult by the time I was born, so we never talked much, and never had much in common, because of the age gap."

"Oh, that makes sense," said Sans. His brow furrowed, and he said nothing else.

It took Gaster a quiet moment to realize his mistake. "Well, I mean we never bothered to find anything in common." He drummed his fingers against the table nervously. "I'm sure if either of us had made an effort, perhaps..." He looked away. "I'm sorry, that was careless. Why don't we change topics? What um, what got you into this field? Why did you decide to become a scientist, Sans?"

"Well, as a kid, there was a point where I was afraid to go outside, so I spent a lot of my time indoors, usually in the library. I started reading science fiction books, then moved onto books about actual science. Mostly books by you, actually. They were really interesting, and I wanted to know as much as I could, so I kept reading and studying, and by the time I got to college, I knew for sure what I wanted to pursue."

"That's wonderful," said Gaster, beaming, "I'm glad I played a part in inspiring you to join my field. But why were you so afraid of the outdoors?"

Sans slouched, looking down at the table. "I was attacked by a dog once. It seems silly now, because it was only a tiny thing. But at the time, so was I, you know? And it dragged me through this hole in the ground, and everything was just so... **dark**. Then it was just gone. Scratched me up pretty bad though." he said, rubbing the outside of his right eye socket.

"Was it a white dog?" asked Gaster, setting his fork down, "A small white dog?"

"Yeah," said Sans, cringing. "Dr. Larkeet told me about that, too, about your little pest problem."

The doctor sighed. "That thing is an absolute menace. It even bit me, once, when I tried to catch it. I've been trying to figure out for years how it, well, it just vanishes, and teleports itself around, or gets _inside my machinery_. I hope it's never gotten into my office. Someone else already has, and they did it knowing I would see it."

"Wait, really? Who did that?"

"Ugh, it's hard to explain." Gaster twirled his fork around and around on the plate, making a noodle-vortex that swirled endlessly. "I can try, though. Do you remember that day I sent you to get coffee?"

"Yeah."

"Well, while I was in the lobby talking to you, I was also asleep up in the office. The Gaster you spoke to is the one who I watched later on the security feed, as he made his way into my office, and never came back out."

Sans's jaw hung open slightly. "And you have a doppelganger, why?"

"I don't. He had both my keycard and my office key, and he never took them from me, and I don't have copies of either. He was me, I'm almost sure of it. And that's a sign that my personal work could be successful. I still don't know how, and his hint wasn't exactly helpful, but I'd like to consider it a good sign."

"Okay, what exactly are you working on in there? Time travel?" Sans asked, his eyes narrowing.

"Yes." said Gaster.

"Seriously? How does that work?"

"Like I said, I don't know. And he wasn't there to tell me. All he left behind was a blue card that said 'Don't be afraid to ask for help.' So, someone else must have the answer. I could show you what I've got so far, sometime, if you're curious."

"That would be great," said Sans, "I'd love to see it."

They spent the rest of their meal chatting excitedly, until their plates were empty and Sans figured it was time he went home. They walked side by side out of the diner, and into the night.

"Would you like me to walk you home?" asked Gaster, casually.

"Heh, I don't think that's really necessary," said Sans, blushing. "Th-thanks for the offer though." He rubbed the back of his skull. "By the way, this _thing_ we've got going, whatever it is? I'm guessing it should stay quiet, right?" He looked up at Gaster.

"I suppose that would be for the best, yes. Although Larkeet already knows, about it, so it's not exactly 'top-secret'. Don't tell your mother, though, I beg you."

"Wait, you told Larkeet? When?"

The doctor looked away. "Well, it was a combination of her weaseling the information out of me, and figuring the rest out on her own," he lied. "She's actually the one who suggested I take you out tonight. She might needle you a bit, but she'll keep quiet to anyone else."

"Wow, okay. Is it alright if I tell my brother?"

"I don't see why not."

"Thanks."

They fell into silence again as they walked, until it came time for them to part ways.

"Well," said Gaster. "I hope you had fun, tonight? It was nice getting to know a bit more about you."

"I did, yeah. I hope we can do this again sometime." Sans said, grinning. "Thanks for the date."

"Any time," said Gaster. Lacing and un-lacing his fingers, he looked away. "May... may I kiss you, Sans?" he asked, his voice tight.

"Sure." Sans whispered, leaning forward slightly.

The doctor reached down and cupped Sans's jaw gently. Sans closed his eye sockets and tilted his head back as Gaster's mouth met his own. He felt warmth flooding his entire body at the brief contact, and when Gaster pulled away, he was shaken, still wanting more.

"Goodnight, Sans." He said, breathlessly.

"Night, Gaster." Sans whispered back.

He walked the rest of the way home in a daze.

 

**Notes for the Chapter:**

> I'm very sorry this took all week to get up. I was a little stuck. Turns out the easiest solution was also the most fun to write! Lucky! :-3   
> I'm sorry about the huge amount of boring dialogue, if anyone has ANY questions, lay them on me! I'm so sorry!


	17. Pew Pew Pshew

"Can you boys take care of the dishes for me? I need to get ready for bed."

"Sure thing, Mom. Have a good night." said Sans with a little salute. He picked up the plates and silverware from the table, while Papyrus grabbed the drinking glasses and took them over to the sink.

When their mother was out of earshot, Papyrus turned to his brother and whispered, "So, you have been acting strangely today. What's going on?"

"Oh, nothing major," said Sans, beaming. "I've just got this huge secret I'm holding in, and there's only one person I can tell."

"Is it me?"

"Maybe."

Papyrus cocked an eyebrow at him and picked up a dishtowel. He began to dry the dishes as Sans finished rinsing them.

"Okay, fine." Sans sighed. "It's been a really weird week. Lots of ups and downs. But..." He turned and looked behind him. "You know my boss, Dr. Gaster?" he asked, voice lowered.

"Yes? I met him, he was rather nice."

"Right. Well, we went on a date last night."

"WHAT? WOWIE!"

"Ssshhhhhh!" Sans checked behind himself again. "Mom's going to bed, and besides that, I don't want her to know about this."

"Are you going to surprise her? When are you bringing him for dinner??" Papyrus asked eagerly.

"I'm probably not gonna. I mean it's nothing serious, not yet anyway," Sans said, "But I guess he knows Mom, and she doesn't like him."

"That's strange, Mom likes everyone!"

"No, not everyone. And she can hold a grudge something fierce, Paps. But I'm not looking for her approval on this." Sans turned the running faucet off. "Or anyone's approval, I guess. So keep this between us?" He looked up at his brother, who nodded reassuringly.

"I can keep a secret!" He whispered, rather loudly, grinning.

"Cool, thanks."

Papyrus wrapped an arm around his shoulders and pulled him close. "I can't believe my big brother is finally in the dating scene! I'm so proud of you!" he said.

"Please don't sound so surprised. I've dated people." Sans grimaced and pulled away.

"No, you ' _studied_ ' with people, and always at their house, never over here. I've never heard of you having a datemate before."

"I had a girlfriend back in elementary school, actually. I'm not sure if that counts." He shrugged. "What about you? Is there anyone you like, Papyrus?"

Papyrus blushed and turned away, placing a dry cup in the cupboard. "No, no there isn't!" He insisted. "And if there was, it certainly wouldn't be the captain of the chess club, who I'm too nervous to speak to already! That would be the worst."

Sans patted him on the back. "You'll get there someday, pal," he assured Papyrus. "If I can do it, you can."

"Hmph."

"Wanna know something? Gaster said you were charming. He thought you were the older brother, too."

"Well, that settles it then!" Papyrus said, turning on his heel and marching out of the kitchen.

"Where're you going?" Sans asked.

"I'm on my way to steal your man!"

"Hey, you think that's funny now, but I'll fight you if you try it for real!" Sans called, marching after him.

"Boys, can you keep it down out there? I really need to sleep!" Called their mother from her room.

* * *

 

"Well, it sure is a surprise to see you here!" Chirped Larkeet as Gaster approached. She sat down on the bench and began to remove her gear. "You weren't holding up a sign!"

"I told you I wouldn't." he huffed.

"Yeah," she said, setting her helmet aside, "but you don't always do what you say you're gonna do. So it was up in the air."

"I get it. Congratulations on your victory, by the way." Gaster said, folding his arms.

"Thanks! HEY MIBBON, NICE JOB ON THAT ASSIST!" Larkeet called out to one of her team mates, who gave her a thumbs up in response. "So!" she continued, turning back to Gaster, "Did you apologize to your paramour for the mood-whiplash?"

Gaster rolled his eyes. "I did, actually. Took him out to dinner and everything. Thank you for the suggestion, we had a lovely time."

"And?"

"And," he groaned, "whatever happens next is none of your business, plain and simple."

She chuckled. "Aww, I'm glad it went well then. I hope I don't catch you two making out on the equipment."

Gaster bristled. "That is not going to happen, I assure you!" he snapped.

"Sure, now that I've brought it up, it won't happen." She winked.

"Stop."

"Yeah, yeah. I should find my husband, before the rest of the team heads out for our celebratory meal. Thanks for coming to cheer me on, Gaster," she said, reaching up and clapping him on the back.

"Of course," he sighed. "I hope to see you early Monday morning!" he called after her.

* * *

 

Early Monday morning, Sans checked the readings from the oscilloscope-still steady- and made his way down to the lab proper, eager to begin the day. Dr. Larkeet and Dr. Gaster were already there, with what looked like every piece of testing or monitoring equipment in the lab, and connecting it all to the cannon.

"Hey, Early Bird!" Larkeet greeted him.

"Good morning Dr. Larkeet, Ga-Dr. Gaster." he replied.

Gaster looked up and greeted him with a slight smile. "Sans, good to see you here early," he said. "Can you attach this thermometer to the wall behind the tarp for me? I need it placed across from the impact sensor."

Sans reached over and grabbed the thermometer from Gaster. Their fingers brushed against each other briefly, and Sans watched the doctor's face flush slightly at the contact. He turned away before allowing himself to grin a little, doing his best to hide his expression from Larkeet.

He lifted the black fabric with his free hand, shivering at the way it rubbed against his bones. He clipped the thermometer to the wall, about a foot away from the piezoelectric sensor plate, but still within the radius of where the canon's beam would hit. Once that was done, he lowered the thick, warm fabric to examine it closely. It was the darkest substance he had ever seen, with no visible indication of its unusual texture. Its fibers gently scratched the surface of his phalanges, and made a sound that he could feel at the top of his spine, rather than hear. He dropped it and watched silently as it sank back to its place against the wall.

"Wow, we really are running tests on this thing, huh?" Wickett called out from the entrance of the room. Sans startled, having not heard him approach.

"We need as much information as possible in a short amount of time." Gaster replied. "So we'll just have to collect it all at once."

"How many times are we going to fire the cannon today?" Juneborg asked tentatively from behind Wickett.

"As many times as possible, without causing an electrical shortage." Larkeet responded. "I'll be keeping my eye on that throughout the day. If you guys want to get your safety gear together, we've almost got everything hooked up."

Six successful shots in eight hours was nothing to sneeze at, especially when one considered the hour-long cooldown period they alotted between each one, and the single misfire they spent twenty-seven minutes fixing, when Alphys showed up right as Gaster had hit the firing switch, and he had scrambled to kill the beam immediately. _At least she had had the good sense to turn away and cover her eyes_ , Sans thought. _And on the bright side, now we know how to shut off the beam quickly in an emergency._

After making sure she was okay, getting her safety equipment set up, and restarting the cannon's control system, they were back on track quickly.

The first two blasts had settings consistent with what they had used on Friday, and with the following four, Dr. Gaster had adjusted the power of the beam, the frequency, and the duration of the blast. With everyone looking over the data from their testing equipment while the cannon cooled down, they discussed and finally settled upon the settings they would use for the presentation the following day. After the final shot, Gaster asked for everyone's help unplugging the testing equipment while he shut the cannon down.

"I would ask that everyone shows up at least twenty minutes early tomorrow morning," he said, addressing his crew. "Please also be well rested and well-groomed." He looked them all over as he spoke. "But don't be nervous. We aim to impress King Asgore, yes, and we will do our best. But with as much as we've accomplished in such a short amount of time..." He gestured to the cannon beside him. "And how promising the results are? I'm certain he'll approve this plan to go to the next stage. Then the real work begins."

Wickett raised his hand. "And you'll inform him of any risks associated with the cannon?" He asked pointedly.

"Yes, I will be sure to do so." Gaster said flatly. "So, why don't we call it a day? All of you go home and get some rest, and I'll see you here early Does that sound alright?"

There was a nodding in agreement through the room, not quite in unison. Gaster smiled, pleased, and signaled them to go.

Sans tried to be discreet as he hung around the entrance of the room, waiting untill everyone else was down the hallway and around the corner before he turned to Gaster excitedly. "So?" he asked, "Are you still going to show me what you've been working on in secret?"

The doctor grinned. "A quick peek," he said, "and then you really should go home and rest. so should I, for that matter." He turned and unlocked his office, letting Sans inside before following him in and shutting the door partway behind them.

Gaster's private office was actually much bigger than Sans had been expecting, although the desks and shelves and the cot near the door all made for less walking space. The room lacked the fluorescent lighting of the rest of the lab, being lit mostly by lamps scattered about, and there were papers and pieces of machinery everywhere. Sans noted one of the tiny, prototype blasters sitting on a table near the back, as well as a magnetic office toy on the desk nearest him. He reached over and tapped the toy gently, and it spun wildly.

The doctor cleared his throat, and Sans's attention was back on him immediately. He brought Sans over to a very cluttered table across the room, covered in books and folders and papers that were held together by colored clips. "You wanted to see what I've been working on," he said, "but at this point I must admit most of what I've done so far is just gather resources and reading material from all over the Underground. I've experimented with a few methods, and documented what I've done, but nothing so far has been fruitful."

"Well, I wouldn't say that." Sans said, picking up a small blue slip of paper from the table and turning it over in his hands. "D'you think I can be of any help? I don't know much of anything about time travel, just what I've read in fiction."

"We'll see how things go after tomorrow. If Asgore approves the cannon, we'll be busier than ever, and finding time to work on side projects might prove difficult. However, you're free to read through any of these," he said, gesturing towards the contents of the table. "I'll even let you take the books home. The reports and experiment logs need to stay here, though. If you want to read them, you'll have to come here after hours or on the weekend."

 _In his office after hours?_ Sans half expected the doctor to be waggling a pair of eyebrows at him, with a suggestion like that. But when he looked up, Gaster's expression was placid. "What do you recommend first?" he asked.

Gaster looked over the contents of the table and pulled out an astrophysics book, and an old, worn book about gravity. "Read these together, especially the bookmarked chapters in that first one." He thought for a moment and then leaned over, reaching in front of Sans to pull a small, bound stack of papers from the pile. "Also, you can take _this_ report home. I know there are a few more copies up at the University, and it's not exactly top-secret information."

Sans set the books down for a moment and took the report with his free hand. "Wait a minute. Did Professor Wickett really write this? The same one?"

"Yes, he did," Gaster replied, nodding, "I told you he's an expert on human magic. That's a good read, by the way. The information therein was absolutely invaluable when I was still figuring out the prototype cannons. I'd recommend anyone who works here to read it." After a moment of thought, he added, "Don't tell Wickett I said that, I don't want to hear him boasting."

Chuckling, Sans placed the report on top of the books, and held his new bundle of assigned reading to his chest. "Anything else while I'm still here?" he asked expectantly?

"I meant what I said about this being a quick peek, Sans. You should get going home."

"I'm just curious, how's your head feeling? You gonna need any help getting to sleep tonight?" He flushed in embarrassment.

Gaster smirked. "That won't be necessary tonight. I'm staying here to guard the cannon from that meddlesome mutt."

"Shouldn't you get some rest too, though? I mean, tomorrow's pretty important for you."

"Please. The day we actually started up the Core? I had gone 36 hours without sleep. I can crash tomorrow night."

Sans looked unsure. "Okay then. Have a good night, Gaster. See you in the morning."

"Bright and early!" Gaster insisted, "If you're late, you might as well not show up." He grinned and walked over to the door, opening it for Sans. The young skeleton stepped through the doorway slowly, turning to say good-night one last time, when Gaster grabbed him by the collar and pulled him in for a brief kiss on the cheek. "Don't be late." he repeated in a whisper before letting Sans go.

The next day, Sans woke up in a panic, worried he'd over-slept and missed the entire workday. By the time he realized it was still morning, he was too jolted to get back to sleep.  
_Nothing better than starting the day early though, right?_ he thought, grumpily. _Three whole hours early._

 

**Notes for the Chapter:**

> Next chapter might be a little short in comparison to this one, but...  
> BUT!  
> we get to my favorite part of the story!!! SHOWING KING DAD THEIR MACARONI ART GUN, SO HE CAN HANG IT UP ON THE FRIDGE!!


	18. Asgore, were you even listening?

**Notes for the Chapter:**

> Sorry for the week-long wait! Golly! I might twiddle around with this at a later date, and move the first bit to the end of the last chapter where it should have been in the first place. For now, please enjoy a longer-than-usual chapter. :'-3

 

The whole team had shown up with more than half an hour to spare, and they spent the time chatting excitedly about the day ahead, while donning their safety equipment and setting up.

"Alphys, dear, we've still got about ten minutes until the king arrives," said Gaster, "Can I ask you to go up to the lobby and wait for him? I've still got a few more things to tweak."

"W-wh-why me?" she stammered. "I-I mean sure. I can, b-but shouldn't you be the one to uh, greet him?"

"That would be out of the norm. I haven't been the one to greet him since I was working for Dr. Marlick. It's usually the intern's job to lead him down here, make small talk, make sure he's comfortable, that sort of thing. He _really_ appreciates it." He smiled innocently. Sans looked over and noted how red Alphys's face was becoming. _Now that's just mean._  he thought about stepping in to save her, from Gaster's teasing, but before he could, she began nodding violently in affirmation.

"I can do that!" she piped out. "I'll just go and greet him and escort him here, it'll be no sweat!" She turned quickly on her heel and marched away.

"That was a bit much, don't you think?" Sans leaned in to whisper.

Gaster quirked a brow at him. "It really is her job though," he whispered back. "If I wanted to be mean, I could shut off the elevator when they're halfway down and leave them there for a few hours. That would be mean."

Sans gaped, watching as Gaster turned his attention to the computer next to him.

 

* * *

 

  
Sans stood just behind Gaster, in the hallway before the blaster room, while they waited for Alphys and the king to arrive.

King Asgore was a very large monster, no doubt about that, but under the low ceilings of the lab proper, he looked enormous. His horns would have only a couple inches of room if he were standing up straight. Instead, he hunched himself down as if he were trying to shrink into the labcoat he had arrived wearing. Apparently he didn't like this area of the lab much.

Despite his cowering posture, he greeted everyone enthusiastically as Gaster introduced them.

"Alright, then!" said Gaster, "Now that the formalities are out of the way, I am all too eager to show you what we've been working on these last few weeks. Everyone turned and filed back into the room, spreading out to give Asgore plenty of space.

He stepped into the room, then took a half-step back when he could see the cannon fully. His eyes were wide, but his brow was furrowed. For the first time, Sans actually felt nervous about his approval for everything they had accomplished so far.

It took a moment for Asgore to gather his thoughts. His eyes drifted up and down the shell of the cannon, then he turned to Gaster and finally spoke.

"What... what is it, exactly?" he managed to maintain a tone of authority in his voice, even through his timidness.

Gaster smiled, his hands laced behind his back. "It's a blast cannon," he said simply, "A **weapon** to break the barrier."

"Oh." Asgore let out his breath, having held it for far too long. He smiled, "I'm sorry, It's hard to tell. It looks almost like a- a skull?" He stepped closer, peering at the top of the cannon's shell. "Are those eyes?" he asked, squinting his own.

"They are. Merely for decoration, of course. It's supposed to look intimidating."

Asgore turned back to the doctor and grinned. "You sure pulled that off!" He chuckled, looking the machine over again. "I'm guessing you're going to give me a demonstration?"

"That we are!" said Gaster.

Larkeet turned to a table behind her, grabbing some safety equipment they had set aside, and bringing it over to the king. "Here you go, your majesty, safety first!" she chirped.

"Now," Gaster began, "what we hope to accomplish here, is to overload the barrier by firing an intense beam of magic and energy at the same frequency with which the barrier resonates. The cannon will draw in a huge amount of power, (a load which the Core can handle, worry not!) and..."

Asgore had already finished putting on his safety gear, but he listened intently while Gaster explained the whole process, nodding along. He glanced over to Sans and Wickett when the importance of blue magic was brought up, now finally making the connection between the cannon and the experiment at the barrier.

"... and so I must ask that you don't look directly at the beam," Gaster concluded. "Even though your goggles will protect your eyes from damage, it may be a little... intense."

"Where should I look, then?" Asgore asked, his head cocked in confusion.

"Try to focus on the top of the cannon's shell, or at the target" Larkeet said, pointing at the tarp across from them.

"Alright, if you're ready, I'll have everyone get in place, behind the tape! Your majesty, please stand over here, behind me," said Gaster, pointing to a taped-off section of the floor. Asgore moved over obediently watching the doctor type something into the computer near him. The cannon came to life again, humming with electricity as the jaw spread open. "On my mark!"  
_Five!_

_Four!_

_Three!_

_Two!_

_One!_

The blast of energy was as intense as ever, filling the room with a roar and weighing down the air around it. This time, Sans watched Asgore, who had tensed up to the wall behind him, his gaze flicking from the cannon's jaws to the point of contact where the beam dissipated into the tarp. His face was set stern despite his frightened posture. He relaxed only eight seconds later, when the cannon was powered down and the jaws of the cannon closed, snapping shut with a metallic click.

All eyes in the room were on Asgore now, waiting eagerly for his reaction.

"That... that was amazing!" I am impressed, truly!" he bellowed happily. He turned to Gaster. "When did you start putting this all together? It can't have been just these past few weeks, can it?"

The relief was apparent on Gaster's face as he answered. "No, the prototypes for this cannon were ready about a year ago, but the core was keeping us all so busy." He guestured to the other scientists standing around the room. "It was only thanks to them that we were able to get this done in time for your scheduled visit."

Asgore looked over the lot of them. "You all did an excellent job!" he assured them, "You've got my approval to move this forward! When to you plan to use it on the barrier?"

"Ah, I'm afraid there's still more to discuss," Gaster interjected, his eyes drifting from Wickett back over to the king. "There are some risks involved with firing at the barrier. The beam could backfire and kill us all, or pass all the way through the barrire and do nothing, the core could shut down due to the huge drain, the barrier itself could explode when it breaks, or it could repair itself within a certain time after being broken! There's really no guarantee at this point that we-"

Asgore placed one of his large paws on Gaster's shoulder, silencing him gently. "Take the time you need, Gaster, there's no rush." He smiled tenderly at the doctor. "I have absolute faith in you and your team. Your cannon is approved."

"Thank you." Gaster replied, quietly. "There are still many improvements and refinements to be made, and I'd like- that is, if at all possible, I'd like your permission for my team to gather some data on the human souls you've collected so far. We'd need to observe them directly, with machinery like what we've got hooked up to the barrier right now."

"That should be fine," the king replied after a moment of consideration. "With supervision, of course. We can schedule something when you are ready."

"Thank you again. I hope we won't let you down."

"You won't, I am sure." He looked confidently around the room.

"Thank you for your support, your majesty." Wickett said with his head bowed.

Asgore chuckled. "Oh, of course. Now, I brought some homemade donuts for everyone. Why don't we go back up and enjoy them? It is just a little too cozy down here, with the low ceiling and all."

There was a murmur of agreement across the room, and they all began to file out.

Unfortunately there wasn't nearly enough room for them to all ride the elevator at once. So, they decided to go up in groups. Larkeet, Wickett, and Juneborg took the first ride up, Sans and Alphys waited behind with Gaster and Asgore, the latter of the two fiddling with the old soda machine.

"Do you need some help?" Gaster asked.

"Ah, no, I think I've got it." Asgore mumbled, opening the can with a loud ' _pop_ ' and gingerly taking a sip. "Actually, do you have a moment? I'd like to speak to you about something before we go up. Privately, if that's alright," he added.

"Sure, sure," Gaster replied. "Sans, Alphys, please excuse us. We should be up shortly after you."

The younger scientists nodded. Alphys turned to Sans. "So, are you excited to be-" she began, but was cut off by Sans motioning her to be quiet. He stared down the hallway next to them as Asgore and Gaster retreated, waiting until they were out of sight and earshot before following them slowly, quietly. He looked over to Alphys with a finger raised to his mouth, she narrowed her eyes and raised a brow in response, not quite clear on why he was eavesdropping. She signed something to him, but he didn't understand her, he hadn't learned much more than the basic sign language in school. He merely shrugged and scooted further down the hallway, focused on what he could pick up of the conversation taking place.

"I just thought it might be nice," he heard Asgore whisper, "I mean I never see you anymore, and you don't answer your phone..."

"I have been busy, as you saw today." Gaster hissed back.

"Yes, I know, so have I. But I still... I still make time for my friends, at least. That is all I want, Gaster. I'm not giving you a deadline on that cannon, you can take your time with it. Take a few years, if you need it."

"It won't take that long."

"But it could! There is no pressure this time! Just don't stress yourself out over it. You look so tired today, and it hurts to see you like that."

"Today was a bit different, I..." That was all the rest Sans caught of the conversation before he heard the distant ' _ding_ ' of the elevator down the hallway behind him. Alphys was waving frantically, urging him forward.

"What was that about?!" She asked as he hopped into the elevator after her. "E-eavesdropping on Asgore?!"

"I was curious," Sans said quietly, shrugging. "So, anyways, how's school going? Getting your thesis ready at all?"

She stared at him in disbelief, shaking her head. "No, I'm putting it off for as long as possible," she said, flatly.

"That's a good strategy."

 

* * *

 

  
The whole team chatted over the delicious donuts, and Sans brewed a pot of coffee for everyone to share as well. Even Gaster had a couple of the sweets, despite his insistence that Asgore should stop bringing them altogether.

At some point when the rest of the group was swept up in conversation, Gaster leaned in behind Sans, pretending to fix the back of the young skeleton's sleeve.

"Help me celebrate later?" he whispered casually. Sans nodded, and the moment was over, and they went back to talking as a group.

After an hour or so of discussion with Asgore about the future of their work, and personal plans for the week, they bid him goodbye and headed back down to the lab to unhook the cannon and clean up.

They were almost finished when Juneborg addressed the group, gathering everyone's attention.

"Since we've gotten Asgore's approval, and we worked so hard," she said, pulling a disposeable camera from her pocket, "I was wondering if we could take a group photo, to mark the occasion?"

"Well, you really should ask me next time before you bring a camera down here," Gaster chided, "but it's an excellent idea. Everyone, line up in front of the cannon."

"Who's gonna take the picture?" Asked Larkeet, situating herself just in front of Wickett."

"Oh, um, I could take it." Alphys offered, "I'm kind of camera shy, anyway."

Gaster summoned a pair of magical hands near his head. "I could take it with these, Alphys," he countered. "Hop on into the shot."

"No, r-really" she said "I'm camera shy, and I didn't actually help much with the cannon. I'd rather just take the photo." At her insistence, Juneborg handed her the camera and got into place with the rest of the crew. Everyone got comfortable as she steadied her hands, readying the shot. Gaster laid his hand over Sans's shoulder and squeezed gently, and Sans smiled wide when the shutter clicked.

**Notes for the Chapter:**

> Asgore has his labcoat custom-made.
> 
> EDIT: Also, next chapter's gonna be a skippable, smutty one.


	19. That's not how you smoke a cigar.

**Summary for the Chapter:**

> I'm sorry, there's no such thing as a better title.  
> This is a ~Saucy~ (smut) chapter, please skip it if you're not into that.

**Notes for the Chapter:**

> PLEASE NOTE:There's an uncommon word thrown in here because I'm awful and I couldn't resist using it. If you're gonna look it up, don't do an image search.  
> I'll tell you what it is in the end notes.

Sans found himself pushed back against the door of Gaster's office only moments after it had been shut, Gaster's mouth meeting his in a kiss, rough and wanting, that left him breathless when the doctor pulled away.

"Wow," said Sans, panting, "you're not wasting any time, huh?"

"Forgive me if I'm a little eager," whispered Gaster, "It took all my willpower to send you home last night, I have none left. And you're hard to resist." He pushed his hips forward into Sans, emphasizing his point. _Damn, what a charmer._

"Heh, you're the one that's ha- mnf" He was cut off by another insistant kiss, Gaster's tongue forcing its way in between his teeth. Sans felt his knees wobble a little bit, but to his surprise, Gaster pulled away and sank down to the floor first, staring up at Sans with eyes half-lidded and hazy.

"Can you give me something to suck on?" he pleaded.

Sans smirked as ideas flooded into his head. That request had been way too open-ended.

"No surprises," Gaster countered with a scowl, "I just want to suck you off. Humor me." He rubbed his palms up and down the outside of Sans's leg bones, and brought his mouth to rest on the fly of Sans's pants, huffing a little.

Sans could feel Gaster's warm breath through the fabric, teasing his pubis with a sensation that was barely there. He quickly focused his magic, and a mere moment later, his erection was pressing against the front of his pants, begging to be let out. He unfastened them and pulled them down along with his boxers, letting his newly-formed dick pop out into view.

Gaster grinned and looked up at Sans, whispering a little "Thank you!" before taking it in his hand and stroking the shaft slowly, wrapping his mouth carefully around the head and giving a gentle suck that made Sans gasp.

He went rigid, backed against the door behind him as the very tip of Gaster's tongue flicked over his meatus, before pressing into the underside of his shaft as he took a little bit more of him into his mouth, stroking the base of the shaft with one hand. He panted, feeling slightly dizzy when Gaster began to suck a little harder. He curled and clenched his fists tightly against the door, pulling his hips back, fighting the urge to buck forward.

Gaster hummed against his head, pulling away for a moment. "You can move your hips, you know. You don't have to stay still," he said sweetly.

"Y-you sure?"

"Mmhmmm." the doctor greeted Sans's cock with his lips again, wrapping them around the shaft and sliding down further.

Sans reached forward unsteadily with his hands as he was sucked on, placing one on Gaster's shoulder, the other atop his head. He gave a few slow, tentative thrusts forward, and when he was met with no resistance, continued at a slow, even pace, dipping himself briefly into the back of Gaster's mouth with every thrust. It felt so good his knees wanted to buckle again, but he held fast, looking down to find that Gaster had, at some point, undone his own pants and was jerking himself off as he tended to Sans, his other hand wrapped around the very base of the skeleton's cock, squeezing gently.

 _Oh god, is he getting off on this? That's..._ "Fuck," Sans grunted, low, breathy, "Doc, I think I'm... I'm gonna-" He tried to pull away, but he was still backed fully against the door. He made an effort to push Gaster away by the shoulders, gently, but was met with unexpected resistance, the doctor using his free hand to grab Sans from behind the hip, pulling him forward eagerly.

Sans hit the back of Gaster's throat three times before he lost it, his orgasm jolted through him, shaking him. Gaster let the whole load pool in his mouth before swallowing in one big, happy gulp, letting out a little moan of pleasure, and finally allowing Sans to slip out of his mouth and slump to the floor.

They allowed each other a brief moment to catch their breath, before Sans dove forward and met Gaster's mouth with his own, tasting himself on Gaster's tongue. He groaned and reached for Gaster's still erect prick, taking over with quick, gentle thrusts that finally sent the doctor over the edge, moaning into Sans's mouth as his cum spilled over onto his lap.

They pulled away from each other slowly, reluctantly. Sans stared in wonder at Gaster's face, still hazy and flushed, grinning back at him. He looked down at his hand, still covered in the doctor's cum, and brought it to his mouth slowly, tongue extended. Gaster pulled it away before he had a chance to find out how it tasted.

"Okay, Sans, don't be weird," the doctor huffed, "I've got a towel around here, somewhere." He rose slowly to his feet, knees still shaking, and looked around him for the towel in question.

Sans took the moment of distraction to quickly flick his tongue over the substance. _Not bad, I've certainly had worse_ , he thought. " _Weird_ would be licking it off of your lap," he said with a grin.

Gaster stiffened in response, towel in hand. He clicked his tongue and wiped his lap clean, before turning to Sans and reaching down to briskly clean his hand. Sans could see the blush spread across his cheeks, and smiled tenderly.

"Join me on the cot for a moment?" Gaster asked. Sans nodded, and pushed himself to his feet, stumbling over to the cot in the corner of the room and flopping down, Gaster sitting gingerly next to him. "That was kind of fun," he whispered, still smiling.

"Yeah," Sans mumbled, "too bad you broke your word, huh?"

"What? What do you mean?"

He grinned. "You said I wouldn't catch you jacking off in here again, and then you did it... right in front of me? I mean wow, how unprofessional." He snickered when Gaster bopped him on the shoulder. "Okay, on a serious note, you said you wanted me to stay over the next time we did something. Do you want me to stay here with you?"

Gaster thought for a moment. "Well, the night is still young, and this isn't all I had in mind when I said we should celebrate... We could go back to my place, have a few drinks, and you can spend the night there, if you like."

"Yeah, that sounds like a plan."

**Notes for the Chapter:**

> MEATUS: the urethral opening of the penis, or just a hole/entrance of some sort into the body.   
> I'm sorry. Sort of.


	20. Later

**Summary for the Chapter:**

> Alcohol mention in this chapter.

**Notes for the Chapter:**

> YOU FOOLS! DID YOU REALLY THINK I WOULD STICK TO A 'TWO PER WEEK' UPDATE SCHEDULE?! DON'T FORGET WHO IS IN CONTROL HERE!!! AHAHAHAHAHA!
> 
> Ahem, sorry about all that. Have some fluff? It's kinda fluffy. Thank you for your patience. I WILL go back to a two-per-week update schedule.
> 
> Also, I drew Dr. Larkeet!  
> http://figsheep.tumblr.com/post/140529937870/i-spent-half-the-day-inking-this-and-then-like-10
> 
> Fun fact: I know her name sounds like a portmanteau of Lark/Parakeet, but while coloring her, all I could think was 'lorikeet, lorikeet, lorikeet!'

Gaster had already been a little tired at the end of the workday, but not quite sleepy. Rather, he was still very excited over his team's success. The glass of wine he was now sharing with Sans on his couch however, was finally taking effect. He was calming down, warming up, but resisting the urge to drift off, as he was still enjoying himself, chatting idly with Sans about this and that.

"It's mandatory for a reason," said Gaster, "I can't believe you don't know any sign language."

Sans winced. "Only the basics are mandatory, the rest is optional. It was just so long ago, and I've almost never had a reason to use it, I just kind of... forgot? Anyways, that's why I picked up a book about it last weekend. I'm gonna try and learn."

"I'll have to remember to quiz you on things from time to time," he said with a smirk. "I've even made signs for obscure pieces of equipment in the lab. Those would be fun."

"Slow down there, Doc. I mean, I've got a lot on my plate now as far as reading things is concerned. I'll make my way through the book at my own pace."

"Alright, alright." He swirled the rest of his wine around in his glass before downing it. He caught Sans's eyes on him as he wiped the corner of his mouth. "Are you excited? We're going to be very busy from tomorrow on, making sure that cannon is perfect."

"Yeah, I'm excited." Sans looked away for a moment, then back. "What's our deadline on that, by the way?"

"We don't technically have one, but I'd like to get it in order as quickly as we can. I can't let Asgore down, you know."

"Heh. I don't think it's possible for you to disappoint him."

"What makes you say that?"

"It's just... Well, I don't know if you saw the way he was looking at you earlier, during the presentation, but I think he had already made his decision, you know? Like, he would have approved your project no matter what."

Gaster bristled, but tried not to let it show. That was the last thing he wanted to hear. "Well," he said, fidgeting with his now-regretfully-empty glass, "Asgore doesn't know much about the technical side of what we do, because that's not his job. If he didn't have faith in us, there would be no point in keeping us on the payroll."

Sans had picked up on th edge in his voice and was now looking down. "You're right, sorry," he mumbled.

The doctor closed the distance between them, leaning over Sans and pinning him against the back of the couch. He grinned at the color spreading across Sans's cheekbones. "I think you're implying that my relationship with Asgore has some sort of sway in whether he approves our work, and you're very mistaken, Sans. The king takes his job seriously."

"Your... relationship?"

 _Of course that's all he heard_. Gaster rolled his eyes. "If you weren't aware already, Asgore and I are good friends, mostly because we've known each other for so long."

"No, I got that," Sans said, reaching up and toying with Gaster's shirt collar. "Just friends, right?"

"Do you have reason to believe otherwise?"

Sans was silent for a moment. "No," he whispered, "Just the way he looks at you."

Gaster chuckled. "Don't let it get to you, he's like that with a lot of people."

"Was he the one you dated, though? Your boss?"

"Sans..." He sighed. It wasn't a very well-kept secret, despite his efforts he was sure several people knew, but that didn't mean he wanted to talk about it. "Yes," he said simply, "I mean, I wouldn't have called it dating, but yes." He wouldn't have called it anything if given the choice. He would have feigned innocence and insisted nothing had ever occurred between them. _But that's not how life works. You can't just undo an entire relationship, no matter how much time passes._

"So-"

"No, that's enough." He put his fingers up over Sans's mouth, gently, to shush him. "I know you're probably burning with curiosity, but it has been a long day, and the effects of that wine are setting in, and I'm too tired for this. Come to bed with me. Or don't, it's your call." He pushed himself off the couch and stared down at Sans, offering a hand out to help pull him up. The young skeleton took his hand without hesitation, and silently followed Gaster to his room.

* * *

 

Sans set the alarm on his phone for an hour earlier than usual; he hadn't brought a change of clothes, and would need to return home before work the next morning. He watched from the corner of his eye as Gaster undressed partially, then climbed into bed. Setting his phone down, he decided fo follow suit.

He slid under the covers slowly, carefully, keeping Gaster at arm's length. Even though this wasn't his first time here, he was nervous, waiting for a signal that he should move closer rather than invading the man's space immediately. His signal came in the form of Gaster's fingers reaching out and gently brushing the side of his arm, making him jump and gasp, because he hadn't seen the doctor's arm move.

"Sorry," Gaster whispered, "just, come closer, please."

He complied happily, scooting in close enough for Gaster to wrap one arm around him, for their foreheads to touch. The warmth of their bodies was beginning to build up under the blankets, creating a cozy space around them.

"Thank you for being here with me tonight." said Gaster.

"Any time."

He entwined his fingers around the doctor's free hand and sighed happily.

"Can I ask you one question, Doc? About Asgore?"

"One, you only get _one_."

"Is... is he bigger than me?" he asked with a grin.

"I'm not going to answer that." Gaster said, flatly.

"C'mon, Doc. I gotta know." He tried to hold in his laughter, but his voice cracked in the middle, giving him away.

Gaster blew a single, sharp puff of air into Sans's face, making him flinch and chuckle lowly. They pressed their foreheads together, smiling and letting their sleepiness overtake them.

* * *

 

The next morning, Sans turned off his alarm and rolled back over, nestling back into Gaster's arms. He wasn't even tired, just far too comfortable to get out of bed. He drifted back off happily, assuring himself he'd be up and out the door in fifteen minutes or so.

An hour later, he was cursing as he quickly pulled on his pants and overshirt, fully aware he no longer had time to shower.

"It'll be fine if you're a few minutes late," Gaster assured him while stretching, "I won't penalize you under extenuating circumstances."

He met Gaster's smiling gaze with a glare. "You think I actually believe you're gonna let me off the hook for this?"

"Do you think you have time to be talking right now?"

"Shit. Okay, I'll see you later."

"Not too much later!" Gaster shouted after him as he rushed out the door.

No shower, barely enough time to change, and he was going to be late to work while his boss laughed at him for it. All for an extra hour of cuddling. _What a fantastic way to start the day._

Given the chance, He'd probably do it again.


	21. Do something!

Twelve minutes. Sans was twelve minutes late to work that morning. By the time he showed up, everyone was already gathered around Dr. Gaster in the lobby, listening intently to what appeared to be a meeting. Until he got through the door, of course. Then all eyes were on him.

"Ah, Sans, so happy you showed up today," Gaster said with a grin as Sans approached.

"S-sorry, good morning." He grimaced and squeezed in between Juneborg and Larkeet.

"Out paryting last night or something?" Juneborg whispered. Sans shook his head silently.

"As I was saying," Gaster continued, "while there isn't exactly an official deadline for when we're ready to fire the cannon at the barrier, I'm setting a soft deadline of 'as soon as possible, and with very few problems along the way', which I do hope we'll be able to stick to. I'm very proud, and grateful to all of you for working so diligently to make the cannon functional in such a short amount of time, and I hope that diligence continues as we tune and refine the machine to fufill its purpose. Now, as for what still needs to be done... " He pulled a small clipboard out of his pocket, and stared it down as he continued to speak, gesturing with his free hand.

"Doctor Larkeet, I'll have you take Juneborg down to the core. The two of you can handle **Project Disco** , I think? If not, tell Poma to help you, since the controls are right by his office."

June's antennae twitched. "Project what?"

"It's an old joke," Larkeet cut in, rolling her eyes, "one that stopped being funny years ago."

"That is the name that was written into the plans for the core, that is the name we will continue to use!"

"That was before Asgore knew about your plan for a cannon. Now that it's not secret, there's no point in using a code name! I think he's figured out by now that there isn't going to be a disco party."

"If the cannon is successful, there will be. I'll make sure of it." Gaster crossed his arms.

Wickett's eyes narrowed. "Is there anything you take seriously around here?"

Gaster glared back at him. "Considering this kingdom's tradition with how things are named, I don't think a few silly titles here and there are going to hurt anyone." He thought for a moment. "And safety, I take the safety of my team very seriously. But we're getting off topic." He held the clipboard back up to his face. "Like I was saying, Dr. Larkeet and Juneborg are going down to the core to initiate **Project Disco**. Sans? How much to you like building things?"

Sans tensed, caught off guard, then shrugged in an attempt at casualness. "A little more than I like math?" he said, uncertainly.

"Good to hear. Because I've asked Alphys to design a smaller, more powerful oscilloscope, and we're going to need at least three of them so we can monitor the human souls the same way we've been monitoring the barrier. I'd like you to help her put them together and set them up, I'll take care of scheduling an appointment for the two of you to do so. After that, you can help me begin disassembling the cannon, so we can move it."

"What about me?" Asked Wickett, gruffly.

Gaster sighed. "I'd like to have you run a few tests on the human souls once we get a reading on their frequency, but until then... just... help Alphys and Sans build those scopes," he said, dismissively. "I'll give you a list of the data we need to gather.

"Fine, when's she going to be done with those plans?"

"She'll be over later today. I'm sure you can find some way to keep busy for a few hours. I'll be in the lower lab if you need me. You are all dismissed now, and Sans?

The skeleton tensed again, having zoned out of the conversation partway.

"Meet me in my office later, I need to speak with you."

He shrunk into himself a little, aware of the rapid, nervous clicking of Juneborg's mandibles behind him. "Good luck," he heard her whisper as she turned away.

He made his way up to the office to check on the readouts of the oscilloscope at the barrier. Still normal. Was he seriously going to be punished for this? Or was it just going to be a little slap on the wrist for oversleeping? The doctor had found it funny at the time, but Sans certainly wasn't going to test his luck. After all, whatever was going on between them, Gaster was still in charge.

The readouts showed nothing new, as usual. A good thing. He stalled for time at his desk for a few minutes, rearranging things until he figured it was more appropriate to see what Gaster wanted with him. He sighed and headed down to the lower lab.

* * *

 

_Knock knock._

"Who's there?"

"It's Sans."

"Sans who?"

"I thought I was about to be reprimanded. You don't sound angry."

Gaster opened the office door and stared him down. "I have to admit, I'm a little disappointed. You had the perfect setup there, and you didn't take it." He motioned for Sans to step into his office, closing the door behind them.

"I'm really not sure if I'm actually in trouble or not?"

"You're fine today, I got to use you as an example. As long as everyone thinks I've yelled at you, we're good. Do not make a habit of being late, though, or I really will punish you." He plucked at the sleeve of his lab coat. "Maybe even fire you," he added.

Sans chuckled nervously. "Noted. So is there anything you actually need me here for? Or anything I can do until Alphys shows up?"

The doctor thought for a moment. "Well, I've already got Wickett going from room to room, taking inventory and gathering small parts and tools. I'm really not sure what the both of you will need, but it's good to know what we have on hand. I'll be going through the cannon's control program, adding shortcuts for certain settings. That's a one person job... I might have more paperwork that needs looking over! It would be in one of the filing cabinets up in the office. The green one, I think? Second drawer. You'll know it when you see it, it's the folder witth half a dozen coffee mug stains on it."

"Sounds... boring, but doable. I'll get right on it."

"Excellent! I can always count on you to take care of boring, trivial work that I don't want to bother with. You would make a great assistant," he said, reaching for the doorknob.

"Heh, no thanks. Larkeet's already told me what that's-" Sans stopped halfway out the door, frozen in place with an expression of terror. Confused, Gaster peered through the opening to find the cause.

The culprit stood dead center of the next room, watching them, its small body shifting and morphing with every breath. Half of a small wrench hung out of its mouth, directly under a wet, black nose.

"Get..." Gaster was breathless, trying to find simple words fast enough.

"What?" Sans whispered back, unmoving.

The dog slurped the rest of the wrench into its mouth, tail wagging happily at the sudden attention.

"Get that dog!" the doctor shouted, lurching forward, nearly knocking Sans over.

The little white monster bounced around the room as Gaster chased after it, just out of his grasp. Sans watched the two of them, knocking things over and making a mess as he struggled to summon a solution. The sound of Gaster smacking against the side of the cannon as the dog jumped through its maw jolted him, and he reached forward, grabbing the little beast in midair with his magic, and lowering it to the floor.

"I am an absolute idiot, why didin't I think of that?" Gaster asked, rubbing his head in irritation. The two of them watched the dog scramble around on the floor for a moment, unable to move properly under the weight of Sans's magic. Though it certainly was trying, making Sans expend all his energy to keep it still.

The doctor had only just summoned a pair of magical hands to retain the little monster, when Sans felt his magic reach its limit, breaking as the dog tore free, bolting forward into the black tarp hanging on the wall next to it.

And slipping into the fabric with a tiny, startled yelp.

The two of them stared at the fabric in disbelief, listening to the sounds of rustling and growling coming from within the pitch black fibers as the dog shifted about.

"Is it... is he stuck?" asked Sans.

"I'm not sure," Gaster admitted, his eyes fixed on the tarp, "Do me a favor, won't you? Go and find Wickett, quickly. Please."

"Sure, what for?"

"I don't actually know how to remove an enchantment. Never thought I'd have to. Go. Now."

**Notes for the Chapter:**

> late chapter is late. I'm kinda running WAY off of my outline at the moment, so I kind of have to... rehearse things in my head before I can write them? Sorry bout that.


	22. Hair of the Dog

"How the hell did you manage this?" Wickett demanded as he marched into the room with Sans in tow.

Gaster looked up from the base of the tarp, where he was crouched. "I don't know how it got down here, honestly," he admitted, "but I was trying to catch it, and it slipped! Right into the fabric of the tarp!" He rose to his feet and gestured wildly at the fabric. The dog could still be heard shuffling around, letting out an occasional whimper.

"And you don't know how to undo your own damn enchantment to get it out of there?"

"Not safely, no."

"Alright, lemme see what I can do."

Sans and Gaster stepped back behind Wickett as he broke a strand of hardened wax from the side of his arm. He summoned a small flame with his magic, and held the strand of wax over it, letting it melt and drip onto the tarp. They watched the droplets sink into the surface of the fabric, disappearing slowly as they were absorbed.

Nothing happened. The barking and shuffling of small paws ceased. Wickett stepped back, in line with the other two scientists, and they watched the tarp closely for signs of movement.

"Did that not work?" Gaster whispered

Their answer came in the form of a soft GLORP, as a white puddle began to form and spread at the base of the fabric, sliding across the floor toward them. A small black spot appeared in the center, rising upwards to form a snout, then a pair of furry white ears.

They backed up to avoid stepping in the edges of the puddle as they watched the rest of the dog rise up out of it, its fur absolutely dripping with the viscous fluid.

Gaster formed a pair of hands that clutched quickly and firmly around the dog's middle, holding it in place. "I have no idea who you are, or how you keep getting into my equipment, but I want you to **stop** ," he growled, looming over the pup. It looked back up at him and barked happily before launching forward, sliding easily out of Gaster's magical grasp with its slippery coat. It hopped past them to the doorway, where it disappeared instantly.

The three of them stood, awestruck, Gaster's magical hands still clutched around nothing.

"Should I get a mop?" Sans offered as the Doctor's expression fell.

Gaster said nothing, only continued to stare.

"I'd hold off on that, kiddo," said Wickett, "Dr. Gaster might want to get a sample of this stuff and figure out what it is. It's... weird, for sure." He kicked at the fluid on the ground, looking it over.

"Yes," Gaster mumbled, unmoving, "let's do that. Let's..." He trailed off as a pattering of feet came towards them from the hall.

"Dr. Gaster! A-are you here?" Alphys called out.

"He's here!" Sans called back.

"Oh! Looks like almost ev-everyone's here!" She exclaimed happily as she approached. Her smile fell as she got a better look at the room ahead of her, at the gloopy puddle on the floor, and Gaster's stricken expression. "What, um, what happened?" She asked, taking a step back.

"A dog broke in, melted, and teleported out of this very room," Gaster muttered as he continued to stare blankly at the floor.

"Wait, really? Or is this a j-joke?" She hunched in on herself, warily.

"Nope, left a puddle of this stuff everywhere," Sans answered. He looked to the papers in her arms. "Whatcha got there, Alphys? Plans for the mini-scopes?"

"Oh! Yes! Um," She stepped carefully around the goopy puddle, closer to Sans and Wickett. "I d-don't know for sure if everything you need will be here, like gold wire-"

"I've got some," Gaster mumbled softly.

"Oh, okay, well, I mean if there are any parts that you don't have, or can't find three of, let me know. These three scopes should be identical, so maybe start building them in tandem? I'll be back a-after class to help out." She handed the blueprints to Wickett, who passed them to Sans. "Are you going to be okay, Doctor?" She asked, turning to Gaster.

"I'm just incredibly upset," he said, returning her gase solemnly "Thank you for getting those plans done so quickly," he added.

"Of course! That's my job, eheh," she said waving him off as she made her way back to the exit. "Well, um, I need to get back to class ASAP, my break's almost over. I hope you feel better, and I'll see you all late-EUGH?" She gasped as her foot made contact with the puddle. "Ugh??? Why???"

Wickett pulled a handkerchief out of his pocket and handed it to her. "Be sure to wash that off completely, we don't know what it is," he warned.

She grimaced, nodded, and wiped her foot off thoroughly before she left.

* * *

 

Wickett had taken a large sample of the goop off to another section of the lab proper, to find out what it was, leaving Sans to look over the scope blueprints, and Gaster to sulk and clean up the mess.

"For real though, Doc, you gonna be okay?" Sans asked.

Gaster sighed and wrung the mop out into a bucket. "Yes, I just can't believe the damn thing has been teleporting into the lab all this time. How am I supposed to prevent that?!"

Sans set the plans down on the table in front of him and shrugged. "No idea. How the hell does he even teleport in the first place?"

"Well, it's... I um, I don't know for sure, actually. You'd have to ask Professor 'Runs Off And Doesn't Help Clean This Mess Up'. He's down the hall, there, somewhere. Probably using one of the microscopes."

"I asked if you wanted my help with the mop," Sans said, cringing.

Gaster scowled, and summoned another pair of hands to help him move the water bucket over. "I know, I don't actually need any help, I'm just moping. It's frustrating, is all. I almost had him, too."

"Yeah, sorry about that. I'm not used to using that kind of magic, I lost my grip on him."

"It's not your fault."

"Not yours either, he kinda caught us off guard. But uh, if he shows up again," Sans walked over and placed his hand on the small of Gaster's back, making sure he had the doctor's full attention before summoning his own pair of magical hands. "I got your back." He winked and the hands drifted over, taking the mop from Gaster and wringing it out, then passing it back to him.

"Good to know," Gaster replied with a smile. He turned and checked down the hall, to make sure they were alone, then brought his mouth down to Sans's cheek to plant a quick kiss, which made them both blush. "Now, get back to work!" he added with a wink of his own, "You're not being paid to stand around and make jokes."

"Someday, though." Sans said longingly. He took Alphys's plans in his arms and left the room, stopping briefly at the doorway to look it over before passing through.

* * *

 

"Wow, you've got pretty much everything you need," Said Alphys, looking over the spare parts Sans had gathered.

"Yeah," he said, "except..." He scrolled over the plans with his pointer finger. "Ah, except this, and these here, he said, pointing to several parts. "And we've only got one of those screens, I think."

"Oh, yeah. I didn't think you'd have those specific ones. I can grab some things from the university's lab, I know we have a few there. You won't need them right now, anyways."

"Alright, cool. So, we can get started? You may have to walk me through this, I've never built an oscilloscope before."

"Yeah, that's what I'm here for! These are actually going to be really s-similar to the big one, I don't know if you've ever had the chance to look inside it, but it's pretty cool- Oh! Would you mind getting the soldering irons ready? And um, wet the sponge for them, if that's okay?"

"Sure, be right back."

By the time he returned with the freshly-wetted sponge, Alphys had all available parts lined up with their respective machines, and (as she told him) arranged in the order they would be soldered into place.

"You sure know your way around stuff like this," he said, awestruck.

"Well, I'm pretty good with electronics in general," she said, casually, "that and networking. They're a little similar, actually. Just, connecting something from point to point." She soldered a resistor into place on her scope, and Sans followed suit on the one in front of him. "Kind of like, doors and hallways in a building, I guess, letting people flow from room to room, and anticipating how long they're going to be spending in each room, and what they need to do while they're in there."

"It's one of those things that makes less sense the more you try and explain it. I know how electricity works, I went to the same school as you."

"Well, yeah, okay, fine. Jeez." She scoffed. "...So, um, was there really a dog, or were you guys pulling my leg earlier?"

"It was real. Small, cute, terrifying, and real. I watched it swallow a wrench." He said, shuddering. "It's the same thing that chewed up the cannon's power supply last week, so I'm not entirely surprised."

"That's... wow."

"Yeah, it was a little beast. You should have seen Gaster chasing after it though, it was kind of cute, like those cartoons from the surface, the ones with the cat and mouse. You seen 'em?"

"Yeah, I think I know which ones you mean. That's kind of funny."

"It was. He's still kinda pissed though, so don't tell him I said that."

"My lips are sealed."

* * *

 

At the end of the day, Sans headed back down towards Gaster's office, hoping to speak with him there. From a distance down the hall, he could hear Gaster's voice, along with Professor Wickett's.

"I don't know, Wickett, are you sure?"

"Not completely, no. But I've been testing that sample for hours, and that's the only thing I can come up with. I'll bet you fifty gold that when we get a look at those human souls, it'll be damn near the same."

"That's... sure, fifty gold, I'm in, whatever. It's all just very disconcerting. That thing has been a pest for years, and now I'm learning it's a very overpowered pest. How does a monster even acquire that much **Determination**?"

"I'd sure like to know, myself. I wonder if the barrier would read it as human..."

"Not up close, probably."

"Yeah, but if it did..."

"I don't want to think about it right now, honestly."

Sans cleared his throat as he approached the doorway. "Hey, Doc- Dr. Gaster. We um, Alphys is heading home for the day, and I'm heading up to the office to finish my report. Do you need me to stick around afterwords for anything?"

Gaster sighed and rubbed his forehead. "No, you're free to go when you're done with that. You too, Wickett. We can deal with all of this tomorrow."

"Alright," Sans replied. "See you tomorrow, then. Have a good night."

"You too."

Wickett left while Sans started up his report, going through the day's scope readings and organizing the data. It was routine by now, so it didn't take him long. He was just finishing up when he heard Gaster coming up the stairs behind him.

**Notes for the Chapter:**

> You know, when I set out to write this darned thing, it was going to be mostly romance and almost no fake science, aside from the cannon. Now I've lost my original outline, but that's okay, because we are so far off track that I have time to find it before finishing the story! >:-3  
> It's fun to write, though. I've got *ideas* and *headcanons* for things like 'Dog Chemistry', 'Cooking with Void' and 'How Skeletons Even Reproduce', and I'm looking forward to sharing them with you! Well, two of those things, anyways. ;-3c


	23. Do you mind?

**Notes for the Chapter:**

> KittyHawkMC drew the whole group of scientists together, and I think I'm going to die of loving it too much!  
> http://kairiblogs.tumblr.com/post/142273996364/its-done-this-is-based-on-a-fic-on-ao3-called
> 
> Thanks, Kitty!
> 
> And thank you all for your patience.

"I had figured the mutt would need to teleport to get into the places it does," said Gaster, "but I've never actually seen it happen before today." He approached Sans's desk and leaned against it, rubbing his forehead heavily.

"Kinda weird that he let you chase him around, if he could escape so easily, huh?" Sans asked, "I mean he let himself almost get caught twice before getting away. What a little shit."

Gaster huffed in agreement.

"Your head okay?" Sans leaned back in his chair, looking up at the doctor, who had his face turned away.

"I'm always going to be stressed, and it's always going to take some sort of toll on me, whether in the form of migraines, or being tired, or both at once" Gaster said quietly, "that is part of the job, it's how things have been for the past twelve years, and even a little before that. I'm not going to ask you to jump into bed with me every time I get a headache, or have a bad day."

"Doesn't mean I can't offer some sympathy, does it?" Sans asked. He could feel his cheeks growing warm. "Or maybe a backrub?"

"You can," Gaster assured him, still looking away, hunching in a little. He turned his head to Sans warily. "I would appreciate that, to be quite honest."

Sans chuckled and got up from his chair, offering it to Gaster. The doctor straddled the back of the chair as he sat down, and Sans began rubbing small light circles over his shoulders, working downwards slowly. He watched Gaster's face from the side as he worked, furrowed brows and clenched eyes slowly relaxing, and he smiled.

"I'm still willing to stay late, by the way," Sans whispered as he rubbed his digits over Gaster's spine, "weekends, too, if it means we get more done. I know the cannon's our top priority, but... Well, honestly, I'm just really curious about how that dog teleports. I'd like to try and find out."

Gaster hummed softly, not quite in response.

"If I could do that... Well, I probably would never be late to work again." He saw Gaster smile silently at that. "Of course, I still want to help you figure out time travel, too."

"Maybe we can teleport through time," Gaster joked.

Sans laughed, low, quiet. "Maybe."

* * *

 

When his hands began to grow tired, and Gaster looked like he was about to fall asleep, Sans stopped massaging and helped him up, bidding him good night with a kiss on the cheek. They parted ways and he went back to his apartment, shutting the door behind him with a weary sigh.

Only a few weeks had passed, and already so much had changed for him. On one hand, he now had much more on his plate than he had signed up for. On the other, it felt good to be busy, and to be... well, _getting busy_. With luck, and diligence, maybe he could keep it all balanced in the weeks to come.

He sat down at his desk, pulled out the books Gaster had given him, and flipped one open to where he had left off, an early chapter about black holes. Sans made it through a few pages easily before his mind started to wander, thinking instead about the vanishing dog, how the creature that terrorized his childhood could have reappeared at any time for a second taste of him, his worst fears confirmed.

No. He closed his eyes tight and took a deep breath, steadying himself. The dog was a menace, but not terrifying. After all, Sans was still pretty small in adulthood, but that thing was tiny. And with its ability to jump into nothingness and skidoo into hanging wall tarps, it should be more fascinating than scary.

Turning his attention back to the book, he tried to focus. One problem at a time. When his thoughts began to drift again, he sighed and turned on the radio next to him, tuning through the handful of stations casually, until he heard his mother's voice. He fiddled with the dial until he could hear her clearly, and listened while the radio played a repeat of her morning report. Her deep voice resonated with him in a familiar way, and he relaxed and smiled, listening to the day's events as he continued to read.

"-seeds that she scavenged from the dump in Waterfall, and will be attempting to grow them using a combination of magical and artificial light. If she's successful, we may look forward to an abundant crop of acorn squash showing up in the Snowdin shop this spring. Won't that be wonderful?"

"In other news, the mysterious red lights some of you have reported seeing at various places throughout the underground have been investigated, and identified as a prank conducted by none other than the Riverperson, who has been found with a laser pointer, which is essentially harmless. When interviewed, they said traffic has been slow lately, and they were bored, and decided to make their own fun. Since the prank was harmless in nature, authorities aren't going to take any action, but the Riverperson themself has resolved not to do it again, stating ' _It's no fun now that I've been found out_.'"

He began to nod off, carried to sleep by the soothing, familiar smell of old books and the sound of his mother's voice.

By the time Sans woke up from his accidental nap, it was midnight and the news had long gone off air, having replaced by smooth jazz. He rubbed the sleep from his eye sockets, frustrated with himself for drifting off so easily. After getting up and making a quick dinner ( _It can still be dinner at midnight_ ), he turned back to the books with a newfound intensity, and managed to make his way through the astrophysics book in one sitting, taking notes along the way.

He was ready to pick up Wickett's report and start reading that, when he noticed what time it was. He needed to get ready for work.

 _Dammit_ , he thought, _I was on a roll there_.

He got ready in a hurry, and decided to take Wickett's report with him. Maybe he could read it over his lunch break.

* * *

 

Sans worked diligently on the mini scopes througout the day, with Wickett's help, there was a lot of progress being made. But they could only get so far until they were stuck waiting to hear from Alphys about the rest of the parts they needed. They kept busy just until their lunch break rolled around, and Sans headed up to his desk in the office, deciding to spend his break drinking coffee and reading that report.

Or he would have, if Wickett hadn't spotted him.

"Is that what I think it is?" the waxen monster asked from behind him.

Sans jumped, nearly knocking his coffee everywhere. "Gah! Sorry, I wasn't expecting you to be reading over my shoulder." He glared up at Wickett, attempting to cover the paper with his fingers.

"No, that totally is, I wrote that!" the professor continued. HIs head cocked to the side slightly and he smirked. "Why are you reading that? It isn't for a class, is it? I thought you were done with school."

"It caught my interest," Sans lied, in an effort to protect Gaster's pride. He looked down at the report, then back up at Wickett. "And I figure it might be relevant to the work we're doing right now."

"Oh, you bet your ass it is," Wickett assured him. "You know about the previous royal scientist, right? Dr. Marlick? Half of what's in that report is based on their research on the barrier and the composition of human souls."

"Really?" I am trying to read, please.

"Yep, that and a _very_ old book, I've listed my sources in the back there-"

Sans thumbed through the thick stack of papers and peaked at the penultimate sheet, Wickett's works cited page.

"-gosh, it's a practically ancient thing, about the kind of magic humans were using at the time, before the war. Great book, I'd recommend it. Gives a bit of insight as to the magic we're up against, and if the seven mages who cast the damn thing were even half competent, then I'm not just talking about the seal of the barrier itself."

"Yeah, what then?" _I would probably find out if you'd let me finish reading, but hey!_

"Well, based on everything I've come across? I'm pretty sure the barrier knows when there's a human in the underground."

"It... knows?"

"Yep."

"Why?"

"Well, so they can have an **advantage** , of course! If a human ever makes their way down here, they'd be surrounded by monsters who, supposedly, would do anything to get their mitts on a human soul. So the barrier acts out when it senses a human, and gives them certain advantages, to make sure they don't fall prey. Of course, it wasn't enough to help the five that have fallen down here in the past, but keep in mind that every one of them so far has been a child, and most of them did some **damage** along the way."

"What if more than one human comes through at once?"

"Hasn't happened yet, but I'd bet the barrier would focus on the strongest human that shows up."

"That's nuts."

"That's not even half of it."

"Wait, I heard you talking to Gaster yesterday, about that annoying little dog, and you said the barrier might read him as human? What then?"

Wickett scratched his chin. "Well, I doubt he would actually be able to get through, he's still a monster, after all. But... if the barrier is handing out party favors to humanity, and there aren't any actual humans to pick them up, then he might be collecting them in their stead. My best guess, anyway. It would explain some of the freaky shit he's capable of."

Sans slumped in his chair a little, his head reeling. "Yeah, I suppose." He looked back at the report sitting on the desk next to him. "Any other crazy things the barrier does?"

"Oh yeah, probably. It's difficult to gather information, because it's a passive enchantment for the most part, and it's hard to observe it in action. One thing I do know though, based on what that book says, is that even human enchantments don't last forever on their own. They need a source of power to keep going."

"Heh. Imagine the size of the battery that keeps this mountain going." Sans allowed himself to smirk at the thought.

"It's us, actually.

"Wh-" His smile dropped.

"All our magic, trapped under here with us? Keeps it going. As long as we're down here, it stays up."

The lights in Sans's eyes went out as he stared ahead, taking in that information.

"Anyways," Wickett continued with a shrug, "it's an outstanding book, I should see if I can find it, if you're really interested in this kind of thing, I could let you borrow it for a bit. But yeah, I should get some lunch while I've still got time. Let me know what you think of the report when you finish, eh?"

 


	24. Charmed, I'm sure.

Sans slumped back in his chair, finally finished with Wickett's report. He had gone a few minutes over his break time, thanks to that informative little interruption by none other than the author himself... but he had forgotten to actually eat lunch, and so was doubly annoyed. He chugged down a cup of coffee before making his way back down to the lab proper, report in hand.

Humans, he decided, were definitely the most despicable creatures on the planet. (Years later he would encounter mosquitoes and change his mind.) There was a tiny, flickering ember of hopelessness that had nestled inside of him when he had heard Wickett's words, but he did his best to ignore it, pushing it aside in favor of a desire to succeed. If monster magic was keeping the barrier active, monster magic could take it down.

He made his way down the hall towards the workroom where the mini-scopes were waiting, but at the last moment, changed his mind and headed towards Gaster's office. There was no progress to be made until they received the rest of the parts they needed, so why not see what Dr. Gaster was up to?

From down the hall, he could see the black tarp spread out on the floor of the blaster room, and Gaster standing over it with a look of concentration, fingers twitching. Sans slowed his march and walked slowly up to the room, trying to catch the doctor's attention without startling him.

Luckily, Gaster must have seen him in his peripheral. He put his hands down and smiled as Sans approached. "Is there something you need, Sans?" he asked.

Sans waved the report in his hand. "Just got done with this, wanted to bring it back to you. Finished one of the books, too, but I left it at home."

"Wonderful! I can't wait to see the **notes** you've been taking while you read."

"Oh, I left those at home, too. Sorry."

Gaster's posture straightened suddenly. "You mean you actually have been taking notes? I was just trying to mess with you."

Sans shrugged, allowing smugness to seep into his expression as he grinned. "I guess you underestimated my dedication," he said.

"I suppose I did." Gaster smiled, his expression softening. "Come stand behind me, so I can finish re-doing the enchantment on this, won't you?"

Sans obeyed, treading carefully around the edges of the tarp as he moved behind Gaster. He set the report down on one of the tables behind him. "You don't want Wickett's help for this?" He winced as the words left his mouth. Luckily, the doctor didn't look upset at this question.

"This part I can manage," he said, "but I'm inexperienced when it comes to undoing complex enchantments, and I didn't want to dust the dog, just get him out. Although..." he trailed off.

Sans chuckled nervously, and quickly attempted to change the subject. "So, what kind of enchantment is this, that it's so complex?" he asked.

Gaster's expression lit up. "Well," he began, "the enchantment itself is actually pretty simple, but the process is a bit more complex." His hands began waving excitedly, forming gestures Sans still wasn't familiar with. "You see, the tarp is made up of very densely coiled fibers, and it has a huge amount of surface area because of that. Most of what I need to do is increase the potential space **in between** the fibers, without actually _moving_ them. That sounds difficult, I know, but it's actually one of the things that comes naturally to me." He turned his attention to the tarp. "But because there are so many fibers, and a huge amount of surface area, it takes either a lot of time or a lot of focus, to get the whole thing. Come, feel the fabric before any enchantments are put on it," he said, bending down and picking up one corner.

He reached out hesitantly for the fabric, anticipating the dreadful way all those coiled fibers brushed against the texture of his bones. This felt different than the last time he had touched it, not as scratchy, and definitely less warm. He allowed the fabric to drop from his fingers, and move himself back behind Gaster.

"Alright," the doctor said, "please observe."

Sans watched Gaster's fingers twitch, his brow furrowed in concentration, as the enchantment drifted down from his hands to the tarp. The colorless magic swirled around like heat-shimmer, dancing over the surface of the pitch black fabric before darkening and sinking in, flowing outwards to each corner.

"Wow," he whispered. Gaster smiled as he worked, still focused.

He let go and a final ripple of magic swirled over the fabric, vanishing with a twirl. He turned to Sans with a pleased huff and a grin. "Alright, Sans," he said, "go over and feel the tarp now!"

Sans stepped forward and reached down, picking up the same corner of fabric and pinching it between its fingers. Ah, this feels more like last time, he thought. The itchiness had returned, and although the fabric wasn't any warmer, it felt much _heavier_ than it had just a couple of minutes prior. He let it drop from his fingers and turned back to Gaster, who was still looking quite pleased with himself. "That was pretty cool," he said. In reality, it was a combination of really cool, and kind of cute the way Gaster looked so proud about it.

"Now, will you help me hang it up?" the doctor asked with a smirk.

He looked back to the wall where the tarp had been hung previously, and then back. "I honestly don't think I can reach that high," he said with a shrug

"I know, but it would be funny to see you try." He summoned a pair of hands to the tarp, directing them to lift it by two corners, and attached it neatly to a pair of corresponding hooks high on the wall. He then walked over and attached the center to a hook between them, then smoothed out the surface of the fabric, seemingly unbothered by its scratchy texture.

Sans was struck with a curious thought. "You ever use that kind of enchantment on anything else?" he asked, shoving his hands in his labcoat pockets.

Gaster looked back over his shoulder as he continued to smooth out the tarp. "Like what?"

"Like, the barrier, or the pages of a book, or my closet, which is incredibly cramped.

The doctor laughed. "Well, once with a book, when I was very young. Not the same enchantment, but something similar. All that did was seal the book shut, I could never open it again. Other than that, just towels and tarps."

"How about creating a space between the barrier and the mountainside?"

Gaster thought for a moment, turning himself all the way around to face Sans, placing one finger on his chin and rubbing idly. "That sounds far too simple to not have been tried before," he said, "But the barrier isn't a door cut into the mountainside, it runs all the way around and through the walls of the mountain, sealing off any potential exits. I'm not sure there would be an edge to squeeze through. But I get what you're saying..." He turned and walked over to the storage closet next to the cannon, pointing one hand at it. "It would be as simple as expanding the space between the door and the doorframe, yes?" He focused and allowed his magic to flow once again, swirling around the edge of the closet door, darkening, and slipping into the rectangular crevice. "And if that impossibly small space was wide enough, monsters could slip through. It doesn't sound like a bad idea." He placed his fingers in between the door and frame. "But..." His hand slid into the space, "Oh? that worked?"

Sans jolted and hurried over to where Gaster's hand was slipping between the two structures. "No way. Does that hurt?"

"Not at all, it feels... dense... and somewhat pleasant." Gaster marveled at the sight, half of his hand sinking into a space it shouldn't be able to fit. He wiggled his fingers, then slid his hand back out. "Interesting..." He reached for the doorknob hesitantly, grasping it and stilling for a few moments before he found the courage to twist it and pull the door open.

They both stared. The space inside the closet was much too dark; and what light fell in from behind them was swallowed by the enchantment before it could touch anything within. Gaster reached forward again, but Sans grabbed his hand before it could make contact with the darkness ahead.

Instead, the skeleton reached into his labcoat pocket to pull out a piece of scrap paper. Crumpling it up quickly, he chucked it forward.

It vanished. They listened closely, but neither heard it land.

"Interesting," Gaster mumbled absently.

Both of them jumped when Wickett's voice carried down the hall towards them. "Sans? You in here? Alphys just showed up, and she's got-"

They panicked. Gaster grabbed the doorknob and slammed the closet door shut, pressing his back to it. Sans stepped quickly to the side, just as Wickett came through the doorway.

"What... what's going on here?" the waxen monster asked.

" **Nothing**!" Gaster answered quickly. Sans shrugged and took another step back.

Wickett's brows scrunched together and he squinted, staring them down. "Right... well, if you two are done playing 'seven minutes', Alphys brought the rest of the parts we need." He looked them over again. "I'll be down there working on them, if you want to join me," he said, backing out the door.

"Sounds great," Sans rasped, "I'll be right down, the seven minutes are uh, almost up." Wickett was probably joking about that, but Sans could still feel his cheeks growing warm. Gaster said nothing, glaring back at the wax monster as he backed away.

After a moment, Gaster walked over and checked to see that Wickett was all the way out of earshot. "I'm going to undo that enchantment," he whispered, "for now."

"You don't want to find out what-"

"Later. We still have work to do." He walked back over and placed his palm against the doorframe, allowing a lighter colorless magic to flow from his digits and sink into the crevice. "I need to find that piece of paper first, if I can. I also don't want anyone looking for spare pliers and accidentally walking into there..." Once the disenchantment was complete, he opened the closet door again, peeking inside.

"But... we're gonna find out what that was, right?" Sans shrunk into himself a little. He was burning with curiosity, but if Gaster said to leave it alone, he'd obey. Probably. Or he'd have to copy the enchantment and figure it out in his free time.

Gaster turned to him with a serious expression. "Oh, absolutely. We're _scientists_ , we can't just ignore something like that."

Sans sighed, relieved. "Thank goodness."

"Alright!" The doctor clapped his hands together and walked over to the table where Sans had placed Wickett's report. He tucked it under his arm. "Take care of what you need to, and at the end of the day, come. See. Me. Because I won't be dealing with that alone. Understood?"

"Understood!" Sans hurried off down the hall. The sooner he finished his work, the sooner he could find out what the hell was going on with that dark space. He stopped in his tracks when he saw the crumpled piece of paper on the floor just ahead.

**Notes for the Chapter:**

> Okay, author headcanon time! I don't think I'll ever explicitly state this in the story, as it may never be relevant... but you know (I hope you know) how Sans's 'special attack' is nothing? Well, he's a big booknerd, and doesn't really fight much, so it makes sense that he'd never develop an actual special attack. And every bit of magic he uses is something that Papyrus uses, too. (Which may include the blasters, if the latest patch says anything, but we're IGNORING THE PATCH for this story) So I figure rather than developing and specializing his magic, he's just really good at copying what other folks do with theirs. 
> 
> Which is what he does in chapter 14, (if you've read that) and chapter 22, with Gaster's magic hands. And what he'd totally do if he ever wanted to Do The Voidy Thing we saw in this chapter. NOT THAT HE'D HAVE ANY USE FOR THAT.


	25. Call of the Void

Sans quickly scooped up the crumpled paper and unfolded it to make sure it was, in fact, the same he had chucked into the darkened closet. Yep, same one. A little damp, but otherwise undamaged. He shoved it into his pocket then made his way to the next room. Wickett was seated at one of the tables, but no one else was there. "Is Alphys still here?" he asked.

Wickett was focused on using a very tiny screwdriver to turn an even tinier screw. "She had to go back to class, said she'd be back later."

"Jeez, again?"

"She's incredibly set on getting her doctorate, I'll give her that. Shouldn't matter though, with her instructions we should be able to get done with these today, if not early tomorrow. Although, if the end of the day comes and we're almost done? I wouldn't be averse to staying late to finish up." He turned to Sans. "How about you?"

That wouldn't do. "I've got some stuff to take care of this evening, actually," said Sans. A half-truth. "I say we save whatever's left at the end of today for tomorrow morning, just to be sure we have something to do."

"Good point. If I wanted to sit around with my thumbs up my ass, I'd go home. No one would have to pay me, even."

Sans laughed dryly. "I guess that's one way of thinking about it. Me? I'd rather get paid to do nothing, even if it's boring." He sat down and got to work on one of the scopes, studying the one Wickett had been working on so he could get caught up. They sat in silence for a few minutes.

"Speaking of ' _nothing_ '..." Wickett's voice cut into the quiet like a jagged rock, "...What were you and Dr. Gaster up to?"

"When?"

"Just a few minutes ago, I believe there was a closet involved?"

"Oh, you called it already, we were totally making out." Sans replied with a smile. He doubted the effectiveness of his poker face, resolved to work on it some time, but his tone was even.

Wickett rolled his eyes. "Yeah, sure, whatever." He let the subject drop, however.

Sans laughed to himself, a short, inaudible puff of air. Maybe he could use that excuse more often. Who would believe him if he said that all the time, even if it was the truth?

* * *

 

At the end of the day, with just a little ways to go before the mini-scopes were completed, Sans made his way back to Gaster's office. Doing so without alerting Professor Wickett had been tricky, but worth it. He didn't want to raise any further questions there, after all. So, he had pretended to leave early, then waited in one of the emptier rooms near the elevator until he heard Wickett pass by. He felt pretty cool as he made his way back down the hall. Like a secret agent from one of those human movies.

He halted in front of Gaster's office door, quietly listening for any strange sounds before knocking.

"It's unlocked, come in!" came Gaster's voice from the other side. Sans opened the door and stepped in.

"So, how's it goin?" he asked. Gaster was hunched over a stack of papers, furiously scribbling away.

"I'm preparing some observational notes, I want to know everything about that enchantment and it's effects on larger spaces." He paused for a moment. "And the objects that enter it. I never had to worry about that before, because the only surfaces I used it on were fabric, and nothing large could slip into the spaces between the fibers. Or so I thought anyway, but that **dog** has a tendency to prove me wrong. I can't believe I never thought to use it on a more open space!" He put a hand up to his forehead and rubbed light circles into his temple. "I never did find that paper, by the way," he grumbled.

"Oh, yeah!" Sans reached into his labcoat pocket and pulled the paper out, setting it on Gaster's desk. "I found it in the hallway," he said, "almost fogot about it to be honest."

Gaster plucked the paper from his hands immediately and unfolded it, looking it over intensely. "This is the same one? And you found it in the hallway? Dit it bounce out of the closet, or were you faking me out with that throw? I swear I saw it vanish into that darkness." He held the paper up to the light, attempting to look throught it. No, still opaque.

Sans reeled from the sudden influx of questions. "It's uh, it's the same one. I think. I definitely chucked it in there, not really sure how it got out, or why it ended up in the hall. I say we try throwing more things in, maybe? See if the same thing happens?"

"Excellent, yes." Gaster returned to his notes and jotted something down. HIs handwriting was a mess. "Good. Good. Yes, we'll do that. I also have something..." He stood up quickly and searched around his office. "Ah! Here." Sitting under a table was a small instrument with a pair of rods sticking out one end. He picked it up and handed it to Sans. "We'll use this to measure just how much light that... whatever it is... absorbs."

"Darkness?" Sans offered. He looked the instrument over and saw a small LED situated between the rods.

"As a very plain way of putting it, sure." Gaster waved him off and pulled a thermometer out from under the table as well. "And... Oh, I think my piezoelectric sensor is still out there. We'll need that. When I stuck my hand in, it felt very..." he twirled his hand around, searching for the word, "...well, dense. And static-y."

"You've sure got a way with words, Doc."

"I'm a little worked up, I can't help it. I didn't come in today expecting to have something like this on my plate, but here it is! I don't really have time to be distracted right now, but this is too intriguing to just ignore." He handed the thermometer to Sans. "Thank you, though."

"For distracting you? Hey, any time."

Gaster opened the office door and motioned for Sans to step out. "Well, yes, you're good at that. But I meant for your suggestion. This is new territory for me, and you sort of... led me to it."

Sans felt something pleasant swell within him, like a cool breeze. Pride? Maybe. He watched as Gaster concentrated again on the tight space between the utility closet door and the wall. His magic flowed out and was pulled into the crevice, and they waited until the last of it had sunken in before opening the door. Once again, there was an intense darkness before them.

"Alright, so it's consistent, at least. Will you ready the pressure plate please, Sans?"

"Sure thing, Doc." Sans turned and grabbed the pressure plate and its monitor from their spot on the wall. He turned back to find Gaster with one hand practically jammed into the dark space. " **Hey!!!** " he shouted. Gaster jumped. "Don't just go sticking your hand in there! What if you got sucked in, or something?" He rushed over and pulled the doctor away by the shoulder.

Gaster pulled back, glaring at him. "Oh please, I stuck my fingers into the crevice last time, and I was fine. I don't appreciate your tone, by the way. Or being yanked by the arm like that."

"I don't appreciate the thought of your arm ending up halfway down the hall!"

The doctor's expression relaxed after a moment of thought. " _Touché_ . My apologies for being reckless."

Sans was still bristling, but relented as well. "Sorry for grabbing you so roughly."

They fell into an uneasy silence as Sans readied the sensor, allowing their tension to dissipate slowly, rather than releasing it again in anger. Gaster pulled out his cellphone and snapped a picture of the darkened closet.

"How long does that enchantment last?" Sans finally asked.

"It should stay until it's undone, but we'll see. Is that sensor ready?"

Sans responded by handing it to him, and Gaster slid the plate into the dark.

"Excellent, now we can... wow, that is a lot of pressure."

"Wait, lemme see." Sans stood up on his tiptoes, and Gaster angled the monitor towards him. "Wow, yeah that's a lot. Do you think it's-"

" **Ahem**. S-sorry to interrupt, but um, could I talk to you when you're done, Dr. Gaster?"

The two of them turned, startled, to find Alphys in the doorway. She took a step back.

"Sorry? Am I interrupting something? I just... w-woah, what is that?!" She adjusted her glasses and leaned forward, staring at the inky void that was now occupying what she no doubt knew had at one point been a utility closet.

Gaster handed the monitor to Sans, "The light in the closet went out, Sans was helping me to change the bulb."

Sans snickered at the incredulous grin she gave him. "Do you really think I buy that?"

He grimaced. "Alright, no, you're smarter than that." He turned back to Sans, who could only offer a shrug. "I applied an enchantment to the door to appease Sans's curiosity about something unrelated, and now the closet itself has turned into... this." He waved his arms at the dark space. "I'll explain the whole thing if you have time to help us test a few things, how does that sound?"

She smiled wide. "That's perfect! I actually came by to ask for something to do."

* * *

 

Gaster's eyes hurt from staring into the inky blackness of the void.

Alphys had eagerly agreed to help them after he explained what was going on. He had her operating the testing equipment for him while Sans took notes. This little patch of void had turned out to be very interesting so far. High pressure, low temperature, absolutely no light. He tried shining everything from infrared to ultraviolet into it, and all was absorbed. He wasn't surprised, it acted similarly to the pitch fabric of the tarp.

Unfortunately for him, it was also very _inviting_. He hadn't risked sticking another limb in after Sans had stopped him earlier, but boy oh boy did he want to. To be enveloped by that dark pressure, to explore it and see where it ended...

Better to test it on a few more inanimate objects first.

Sans threw the crumpled paper from last time back in, and they watched it vanish again. He had Alphys keep watch over the hallway, to see if it would reappear. Two minutes passed by, but it didn't resurface. He tried again, with a short length of cord. Holding onto one end, he tossed the other in.

Nothing.

He pulled the cord back out and tossed in a small wrench, reasoning that they should at least be able to hear it land.

They were greeted instead with a high-pitched yelp. Gaster tensed.

"Shit!" Sans hopped back two feet just as the dog came popping out of the darkness, wrench in mouth.

"You!" Gaster shouted. Alphys squeaked. The dog stood before them, wagging its tail. It dropped the wrench at Gaster's feet and looked up at him expectantly.

_No._

"Is that w-what I think it is?" asked Alphys. She clenched her claws tightly in front of her, no doubt nervous from what she had heard about the goopy little beast.

"Yeah." Sans nodded furiously.

Gaster glared at the dog, readying a pair of hands by its sides. "What do you want, mutt?" he growled.

The dog yipped again, before picking the wrench up with its teeth and skipping away, vanishing once again in the doorway between them and the hallway.

He turned his head sharply as he heard it barking, once again from within the dark closet.

The three of them exchanged looks of concern, (well, Gaster could admit his expression was probably one of outrage) between each other, the exit, and the closet. They could still hear it pattering about as its barks receded into the nothingness.

He undid his enchantment immediately. "I think that's enough for the day, don't you?" He asked through gritted teeth.

"Yeah, I'm beat," said Sans. "Should probably head home."

"Are you going to be okay, Gaster?" Alphys asked.

"Fine, yes. We can look into this later." He sighed. _What a day_. "I suppose that little fiasco explains a few things, but... also raises more questions. My head is spinning. Thank you for your help, Alphys, Sans."

"Of course!" Alphys replied happily. "I'm just sorry I couldn't come by sooner, o-other than to drop off parts. Oh!, that reminds me, Sans? How are those oscilloscopes coming along? Are you finished?"

Gaster slipped into his office while the two of them chatted, and flopped down onto his cot.

After a while, the sound of their conversation died away, and there was a knock on his office door.

"It's unlocked, come in."

Sans stepped in and closed the door gingerly behind him. "You OK?"

"I'm alright, just sick of that beast dipping its nose into everything I do."

"Well, we've got an idea of how he vanishes, now, right?" Sans sat down on the edge of the cot and reached a hand out, placed it on Gaster's chest, and rubbed him gently.

 _Oh, that feels nice_. "I think so. It sounded like that... void or whatever it is... is bigger than just the closet. An actual space that can be entered. I'd like to try it some time."

"I mean, I guess if he can come and go safely through it, we should be able to, yeah." He went silent for a moment, but continued rubbing. "Sorry again for yankin' you like that, I was kind of scared, we didn't know if it was safe yet, and-"

"You already apologized, Sans. It's fine." Gaster closed one of his hands around Sans's. "Thank you for looking out for me." He smiled at the flustered look that appeared on the young skeleton's face.

"Hey, yeah, any time."

Gaster smiled and reached up to the collar of Sans's labcoat, tugging at it gently. Sans let Gaster pull him down until their mouths met in a tender kiss.

"We'll explore it more this weekend, how does that sound?" he whispered, "I've had enough excitement for the week regarding that damnable hound."

"Sounds good to me," Sans replied softly. He leaned down for another kiss. And another, and another.

**Notes for the Chapter:**

> I SWITCHED TENSES HALFWAY THROUGH GASTER'S SEGMENT OF THIS CHAPTER, AND ALMOST DIDN'T CATCH IT BEFORE POSTING. HOLY HELL. Writing in the present tense would actually be so much easier for me, but that's not how this story goes. 
> 
> Also, because I love encouraging you guys to talk, I want to do an actual, full illustration of a scene (or two) from this fic? I'm havin a hard time pickin' one though... if you catch my drift ;-3c
> 
> (tell me what your favorite scenes have been so far, because i thrive off of the attention, wink wink)
> 
> ((If you don't want to post it here, you can message me anonymously at ice-cream-salad.tumblr.com, wink wink wink wink wi-))
> 
> And as always, thank you all for your patience, because I've been out of state and was writing something else over the weekend. :'-3


	26. Beautiful, pleasant, INTENSE.

Early the next morning, Sans and Wickett put the final touches on the mini oscilloscopes, amid groggy silence.

"Don't suppose we'll be able to get these set up before Monday, eh?" Wickett mumbled while setting his screen into position. Sans nodded.

" _Actually,_ " came Gaster's voice from behind them, "if you can get them tested and calibrated by the end of the day, Asgore can fit you in, and we can keep them running over the weekend." He stepped in between the two of them, and picked up the scope that was least finished. Sans checked him out while his attention was on the small machine. He looked well-rested, lively. "If you have any preparations to make for the other tests you'll be performing, you should get them squared away quickly, so you'll be ready."

"What's the rush, anyway?" Wickett asked, setting down his tools, "Not like they're going anywhere."

"No rush!" Gaster insisted, "I just want you to be efficient with your time. After all, you need to be escorted to the castle's mausoleum by the new captain of the guard, and she is a very busy woman. Not to mention an angry one. It would be rude to take up her whole weekend making unnecessary trips."

"Oh, that one?" Wickett groaned, "How the hell am I supposed to gather sound-based data with delicate equipment with someone as loud as her breathing down my neck?"

"Wait, who are we talking about?" asked Sans, looking back and forth between the two of them.

"Captain Undyne," said Gaster, "very dangerous lass, very loud. You're probably too young to remember her as the ankle-biter that was always attacking Asgore. She's not the type you'd want around sensitive machinery, but she's the only other person he trusts to keep an eye on the human souls."

Wickett snickered, and Gaster shot him a dirty look.

"She attacked him and he made her captain of the guard? Sounds like a treat, can't wait to meet her."

"Well," said Wickett, "let's get these darn things ready to go, and you won't have to wait long at all."

"Gotta wait for Alphys to calibrate them, unless you know how."

"Frick," said Wickett. "And I suppose she's got class today?"

Sans tensed. "Nah," he said, clenching his teeth, "she's a huge dweeb, no class at all." He had to hold his breath to keep from laughing. Gaster coughed behind him as the words left his mouth, but it took a couple of seconds for Wickett to catch the joke. The professor scowled at him in disbelief, and he finally released loud barks of laughter as tears formed in his eye sockets.

"Oh my god, I walked right into that one." Wickett groaned and slapped one hand to his face, but Sans could see his shoulders shake a little with laughter.

"To answer your question, Wickett," said Gaster, giving Sans a stern look, "She said she'd be around later this morning. I'd wager by the time these are finished. She and Sans can get them calibrated while you ready everything else you'll need, and then the three of you can go to the mausoleum and set up."

"You comin' with us?" Sans asked, leaning over to Gaster.

"I'm meeting with Asgore for lunch, actually." He had his attention turned to his right coat sleeve, which he was pretending to straighten.

"What?"

"We might pop in and see how things are going, though, a bit later on." he said lightly.

"Sounds good to me," Wickett mumbled, picking his tools back up and resuming his work.

Sans squinted up at Gaster, watching him make a show out of how uneven his sleeves were, before turning on his heel and wordlessly leaving the room. _What the hell?_ He waited fifteen seconds before mumbling about needing to go to the bathroom, and getting up from his seat. Wickett waved him off with a 'Yeah, yeah,' as was custom whenever someone said they needed to 'go to the bathroom.'

He rushed down the hall to find Gaster standing against the wall, waiting for him. "I thought so," Gaster said quietly as he approached.

"Hey, um. Not that it's any of my business or anything, but... what the fuck?" said Sans, shoving his hands into his pockets.

"When I called Asgore to tell him we were nearly ready to monitor the human souls, he asked me to lunch." Gaster shrugged. "Apparently he has found a new recipe for snail pie and wants me to test it out."

"I hope that's not a euphamism, because it sounds really lame," said Sans, grimacing.

"I wouldn't have agreed to join him if it was. But he is a friend, and I promised I'd spend more time with him. Is that going to bother you?"

"Not at all." _Yep, just a little._

"Really?"

"But if it **was** a euphamism, what would you do?" Sans winced. Did he sound jealous? He sounded jealous. _Jeez._

"Tell him I'm seeing someone, and demand a real slice of pie."

He stared at Gaster in glorious disbelief.

Gaster smirked back at him. "If you're still worried, I'll have my cellphone on me. You have my number." He folded his arms and walked away.

"But you never answer your cellphone," Sans called after him.

"I will make an exception."

Sans sat back at his seat and got to work, ignoring Wickett's occasional glances at him. He jumped when his phone buzzed from his pocket. It was a text from Alphys.

' _Dr. Gaster said you called me a dweeb? I'm not though???_ '

' _it was a joke. i'm sorry_.'

' _I think you mean_ you're _a joke. And the correct term is Otaku. (^w^)_ '

He re-read the message three times, and decided 'dweeb' was putting it mildly.

* * *

 

She certainly didn't seem upset when she showed up later that morning, to calibrate the mini scopes. Or at least, she didn't seem upset until they started talking about her new favorite show.

"She doesn't sound like a human at all, she sounds like a monster."

"No, no no no. She's a human with cat ears and magic powers."

"Right, and I'm a human with no skin and magic powers."

She put her claws down on the table and thought for a moment."You actually don't look that much like a human skeleton. They're a bit more angular? Their jaws are hinged, too."

"Like my brother's?"

"Yeah! He looks a lot more like a human skeleton. Anyways, we're getting off topic! Mew Mew Kissy Cutie is a masterpiece, and I'd highly recommend you to watch it, because then I'd have someone to talk about it with."

"Right," said Sans, "Where did you find it, again?"

"At the dump."

"In the garbage, yeah. Sounds like a classic."

She rolled her eyes and fiddled with the settings on the scope in front of her, checked her notes, and adjusted them again. Sans watched her closely "You'd be surprised at some of the cool stuff that shows up at the dump, it's not just garbage."

"Maybe I should check it out some time." He adjusted the scope in front of him so it was set the same way as hers, and she moved to the third scope to set that one.

"Why don't you come with me the next time I go down?"

"Yeah, why not?" He shrugged. "I'll pack a picnic or something."

"My my, do I hear two good **friends** talking and making plans to **spend time with each other**?" Gaster asked from behind them as he entered the room. "How pleasant."

"Don't worry, we're staying focused," Alphys assured him, missing the point entirely. Sans groaned. "They're ready to be tested out, and hooking them up to the lab's network will take me f-five minutes."

"Excellent," Gaster replied happily, ignoring Sans's embarrassment. "Wickett's still rounding up tools, I think you'll be ready to go before he is. May I watch you test them?"

"S-sure! Let me just..." She trailed off as she checked the probes were fully connected to their scopes. "Hmm, Sans? Can I use you to get a baseline reading?"

"What?" He sat up straight. "Yeah, just um, stick them on me, right?"

"Mhm! Just um, Oh, where would be good? How about... stick out your hand for me?"

He nodded, feeling Gaster's eyes on him as he held out his palm for her. She attached each of the three probes to his hand bones, and the three of them watched silently as the screens flickered to life with activity, showing a visible representation of the frequency of his soul. The readings took a moment to even out, each stuttering erratically before settling into an identical, steady rhythm.

"Beautiful," Gaster whispered. Sans felt a flush spreading across his cheekbones, and watched the reading change slightly across all three screens; visible evidence that monster souls were affected by their emotions.

Alphys clapped her hands. "Great, looks like they all read the same! I'll get them connected to the network, and then we can pack them up!"

"Good, good. I'll be going, then. Hopefully I'll see you all later." Gaster turned and left the room.

Sans pulled the probes gently from his palm while Alphys dug around in her backpack for something, and stared at the bones of his hands. _He was just complimenting our hard work,_ he told himself. _It was one word, no reason to get worked up._

He was going to have to fight to hold back his elation.

He had no idea what to do if the dam broke.

* * *

 

When Sans, Alphys, and Wickett showed up outside the castle with their equipment, they were greeted by a stern young woman with one eye, bright red gills, and even brighter hair. She glared at them with her arms crossed as they approached. Sans could see Alphys shiver as he walked behind her.

"You must be the nerds I'm babysitting today," the woman said loudly. She grinned, more menacing than welcoming, revealing a maw of long, sharp teeth. "I'm Captain Undyne, of the royal guard, and I'll be keeping an eye on you while you're in the mausoleum. This way." She turned quickly on her heel and lead them through the castle door. They had to rush to keep up with her.

"You gonna be okay, Alphys?" Sans whispered.

"N-n-noooo," Alphys whined under her breath. "Wh-why does s-she have to be h-ho-hot?"

**Notes for the Chapter:**

> So uh... I started drawing some scenes that you guys suggested, the first of which being that kissing scene from last chapter. It is taking a WHILE to ink that one, so maybe I'll just finish the rest of them in chronological order.
> 
> Also, the gap between these chapters has been getting steadily longer, and for that I apologize. The good news is that I cut about a third of the next chapter off the end of this one, so that'll get posted soon. I hope. 
> 
> Oh, and did I tell someone in the comments that this story was about to take a TURN??? I meant Mr. Dreemurr was going to take a turn... at spending time with Dr. Gaster. :-3   
> I was telling the truth though, just a bit longer.


	27. Needs more salt

**Notes for the Chapter:**

> Okay, OKAY. Please let me explain. I reeeeaaaallly wanted to have that kiss scene from a couple chapters ago finished before I posted this chapter.
> 
>  
> 
> [I finished it.](http://figsheep.tumblr.com/post/143982517275/gaster-smiled-and-reached-up-to-the-collar-of)

"So," said Dr. Gaster, smoothing out his coat as he sat down at the table, "I think we can have the cannon ready to go in as little as two weeks. It depends a little on how things go this weekend, but-"

"Gaster, please," Asgore chided, "I really would appreciate keeping the discussion away from work. Just for today, perhaps." He smiled and set a fresh pie, still steaming, down on the table. The doctor stared at the texture of the crust- _so crisp, such a wonderful golden brown_ \- as Asgore slid off his oven mitts and took a seat across the table.

"My life is work, Dreemurr. There's not a thing I do that isn't connected back to the lab or the people I work with. I went to see a hockey game recently, but only because my assistant twisted my arm about it. What have you been up to in _your_ free time?"

"Hmm," He smiled placidly. "I managed to get my hands on some squash seeds from a subject out by Snowdin; I'm going to try growing those. I've been shopping at flea markets around the capitol and found some cute mugs... Oh! I judged a snowman building competition out on the edge of Hotland, just last week! Although I suppose that is work related. Hmm..."

 _Snowmen, in Hotland?_ "How-" _Oh wait, magic._ "How did that go?"

"Rather well, I think." Asgore picked up a knife and began cutting into the pie. An immediate aroma of basil and chives and snails filled the air. Gaster's stomach growled in response, and Asgore laughed, deep and melodious. "Fret not, Doctor. You are mere moments away from what is, hopefully, a delicious slice of pie. Please do tell me what you think of it."

Gaster took a forkful of the pie as soon as it was down on his plate. It was still piping hot, but he ate it eagerly. It was... a little on the bland side, despite the heavy use of herbs. "Salt, maybe?" he thought out loud, "A bit more salt, and I think it would be perfect."

Asgore took a cautious bite of his own slice. "I suppose I must agree with you, there. More salt it shall be. Next time. But please, tell me a bit more about what you've been up to lately, we so rarely catch up."

He thought carefully for a long moment.

"I suppose, if it is all related to your work, then that is fine."

"Ah," said Gaster, "In that case, I've been up to very much indeed. Pest control, mostly but..." He took another bite. _Wonderful, marvelous, so buttery_. "I've been looking into a few new territories, alongside what research we've been doing for the... well, you know, the cannon and everything related to it."

"Such as?"

"Well, I'd really like to try my hand at time travel, if I ever get the chance." He grinned in such a way that the king might take it as a joke.

Asgore laughed, not mockingly, but laughed all the same. "Well, that's a new one," he said, placing his fork down gingerly, "Although, I suppose if anyone could pull that off, it would be you, wouldn't it?" His smile pushed his cheeks up to his eyes. Gaster hated that just a little, how after all these years, Asgore still looked at him so sweetly. "Let me know if that ever works out for you, yes?"

"Of course, your majesty," Gaster said quietly, before taking another small bite of his pie. _After all, I'd be doing it for your sake._

* * *

  
To say that Captain Undyne was intense would have been putting it lightly, but she _was_ silent while they set up their equipment. She watched them from the corner of the room, completely still.

Sans noted she paid careful attention to Alphys, who's nervousness could easily be seen as suspicious behaviour out of context. At one point the poor intern had fumbled and nearly dropped one of the scopes, catching it just before it hit the ground. She brought it up and clutched it tightly to her chest, and flashed a wide-eyed, nervous grin at the guard, who was not amused in the slightest.

"Do you need to step outside, civilian?" Undyne asked dryly.

Alphys shook her head rapidly, almost vibrating. She placed the scope gently down and began setting it up, readying it to be hooked up to one of the souls.

"Does it matter which ones we monitor?" Sans set his own scope down in front of him, looking over the lineup. Each soul glowed faintly in a unique color. He wondered if that meant anything important.

"Not really," said Wickett, "if they all give drastically different results, we can check out the remaining two later on."

Once they had the oscilloscopes hooked up and stabilized, the rest of their day was boring, quiet. Sans and Alphys spent most of the time recording the various results of whatever tests Wickett happened to be running, per his instruction. Sans checked his phone briefly to send Gaster a text message, asking him if he was having fun. Ten long minutes later, his phone buzzed with Gaster's reply of a single smiley face. _How vague_. He sent back a little 'thumbs up' emoji, and shoved his phone back into his pocket.

About four hours in, Alphys had calmed down considerably, and even Captain Undyne was looking bored. She still watched them carefully, but she drummed her clawed fingers against her arms in a rapid rhythm, suggesting she was growing impatient. She yawned, slumped against the wall.

But boy howdy, she stood at attention as Asgore unlocked the door and stepped in, with Gaster trailing closely behind him.

"Hello, team!" Gaster called out as he entered, "how is this little set-up going? Smoothly?"

"Hm. Yeh." Wickett's cocentration on the soul in front of him as he took down a set of numbers was completely unbroken.

"I um, t-think we've pretty much run through all the tests the professor wanted us to run today," said Alphys. "A-all that's left is to keep the mini scopes going over the weekend, and organize all our data into something usef- .... u-u-useful."

"Good, good! I'm guessing you're all just about ready to leave then? I can help you pack up, and we can get you all out of the captain's hair that much quicker."

Undyne rolled her eye and scowled at him.

"Ah, she will be fine," said Asgore, "If it was not clear before, then she knows by now, that the Underground is really not the most exciting place to be a royal guard. But this job is still very important. Thank you, Undyne." He smiled sincerely at her, and she turned her attention back to the other scientists. "Still, it would be a shame if something exciting did happen while she was stationed here. That is always how things seem to go. Isn't that right, Gaster?"  
Asgore clapped his hand gently on the doctor's back. To Gaster's credit, he looked as surprised as Sans felt, and shuffled politely to the side, out of Asgore's grasp. Sans's face felt hot and he turned away, pretending to write down something on his clipboard.

"Ah, that is true, haha. Still, we don't want to keep the two of you from anything more exciting than what we do."

Alphys glanced over to Captain Undyne, then back at the doctor, she nodded eagerly. "I'm looking forward to the weekend."

"I am as well, Alphys. Wickett?"

"Yep, almost done. Gotta just see how this reacts to..." He held out one hand and summoned a complex swirling disk with his magic, letting it sit up against the glass

Captain Undyne took an aggressive stance instantly, her spear at the ready. " **Back away, fuckface!** " she roared. Wickett startled and instantly let his magic dissipate as he pulled away.

"Undyne, language, please," Asgore urged as he stepped in front of her. "I am almost certain he wasn't trying to breach the container, there is no need to be so tense."

Undyne dropped her spear to the side, but kept her eyes locked on the Waxen monster. "You wanted me to guard the damn things," she said, "and that's what I'm doing. I don't take chances."

Wickett looked mildly offended. "Please, you think I'd try and burgle this thing with two boss monsters in the room?? It takes a special kind of stupid to pull something like that."

" _I don't take chances_ ," she repeated. She glanced up at Asgore's stern expression and then back down. "You may resume, but I'll be watching, so don't pull anything."

He huffed and returned his hand to the front of the container, once againr forming the disk with his magic, and allowing it to interact with the resonance of the soul. It spun wildy in several directions, until finally it settled, leveling out at an oblique angle and rotating slowly. The soul glowed brightly in response.

"Ahh, there it is," he whispered. He looked over his shoulder and motioned for Dr. Gaster to come closer. They began whispering excitedly about something, low enough that Sans couldn't make out what they were saying.

Alphys nudged Sans on the shoulder and gestured to the papers and loose tools they had scattered around. He helped her pick it up and stack it neatly while Gaster and Wickett muttered between themselves. Looking up, he noticed both Undyne and Asgore had their attention turned to the two older scientists. Though while Undyne wore an expression of suspicion and concern, Asgore looked like... well, Sans didn't really like the way the king looked at Gaster. He thunked the edge of his stack of papers against the table to straighten them, catching the king's attention. "Hey, thanks for letting us run tests on these," he said lowly, motioning to the room around him.

"Y-yeah, thank you, your m-m-majesty," Alphys muttered in agreement.

"Oh, of course!" Asgore replied happily.

"C'mon, Alphys, let's head out." Sans whispered.

Gaster called after them. "Wait, you two! Wickett, I'll help you get the rest of this gathered, and then we should stop taking up any more of the king or the captain's time, hm?" He looked back over to Sans and Alphys. "We'll be right out, please wait for us."

They agreed and let the heavy mausoleum door shut quietly behind them as they made their way to the top of the stairs.

It was a brief few minutes of idle chatter before they heard Dr. Gaster and Professor Wickett ascending the staircase behind them.

"Sans," said Gaster, once they all met at the top of the stairs, "I've offered to take this paperwork back to the lab, so Wickett can head home, but I could use a hand carrying everything. Could you help me?"

"Yeah, sure." He held out an open hand to Alphys, who gave him her stack of papers. "Thanks, have a good weekend, yeah?"

"You too, I'll let you know the next time I go dump-diving." She smiled and waved as she walked off.

Wickett briefly waved goodbye as well, leaving Sans and Gaster alone in the hall, arms full of papers and folders.

"Let's walk," Gaster said softly, leading Sans in a different direction. They strolled through an empty corridor that echoed every footstep back to them. "Wickett told me how smoothly today went until I got there. Sounds like it must have been boring."

"Oh yeah, I'm sure it was nothing compared to the fun day you had." Sans smiled wide.

The doctor's pace slowed, and he lagged behind Sans for just a moment before continuing forward. "I beg your pardon, but that was probably uncalled for."

" _Probably_?"

"Probably, yes. Unless I've given you some reason to distrust me, there's no need for you to be so- well..."

"So?" Sans wasn't looking at him. "C'mon, don't leave me hanging, Doc. So what?"

"I was going to say petty, but that's not quite right," Gaster muttered, "Jealous. You're acting jealous."

"Yeah."

" _Don't_."

"Ok."

"...that's all? Okay?"

"Yeah, that's all." His chest hurt. What was he supposed to say? ' _I really like this thing we've got going, and I'm not ready to give it up after it_ just _started?_ ' Oh, actually, that would be a really concise and effective way to communicate what he was feeling, yeah. "Where are we, anyway?" he asked, instead.

Gaster sighed. "Well, nowhere. We're going the wrong way. I suppose we should turn back and head out of the castle."

"How are we going the wrong way?" Sans stopped in his tracks. He looked up to see Gaster blushing furiously. "What's wrong with-"

"I um," Oh, he was flustered. "I was going to ask if you wanted to m-make out? In one of the lesser-used hallways... of the castle..." He cleared his throat. "But that was before we started talking. If you'd rather... if you'd rather _discuss_ this, then we should turn back."

Sans took a moment just to stare at him, letting the cold, gripping doubt ebb away slowly, but not completely. "What, here? What if we get caught?"

"Asgore will hear about it, I'm sure." He placed a hand on Sans's shoulder. "I don't intend to upset you by talking with him, but I cannot just-"

"Hold that thought. We can talk anywhere." Sans could put his jealousy aside for a moment, of course. "I think I'd rather make out than sort this out."

"If you're sur-"

"Yes. Yes I'm sure."

Gaster smiled, resigned. "Alright, follow me."

 

**Notes for the Chapter:**

> I'm sure you can guess how the next chapter will start out. ;-3c  
> (They r going to smooch more)
> 
> THANK YOU FOR YOUR PATIENCE.


	28. Lead (me) on.

**Summary for the Chapter:**

> [hey have you heard this song?](https://www.youtube.com/watch?v=P_SlAzsXa7E)

**Notes for the Chapter:**

> First off! Anonymonimuss drew [this cool pic of Sans and Gaster, which I LOVE!](http://ice-cream-salad.tumblr.com/post/144129476618/so-i-actually-had-no-idea-what-scene-to-draw-but) No really, i'm marrying this art.  
> There's gonna be some necking/making out in this chapter, but nothing explicitly sexualllll.  
> Also here's your warning for a bit of jealousy/insecurity content for this chapter... as well as its resolution, for the most part.

Somewhere between Gaster's warm body and the cold stone of the castle walls, Sans's plan to be as loud as possible and get them both caught by a passing guard had fallen apart.

Oh wait, _HE_  was between Gaster's warm body and the cold stone of the castle walls, _HE_   was falling apart. Of course he would turn into a writhing, weak-kneed mess the moment Gaster had him up against the wall, and would forget... forget... oh, it wasn't important. All that mattered was the feeling of Gaster's chest against his, mouth against his, the sound and the feeling of his breath. It felt pretty great.

Gaster had one hand planted to the wall to steady himself, and one hand on Sans's shoulder, gripping him tightly. _There's no need for that_ , Sans thought, _I'm not going anywhere_. He sighed contentedly and ran his hands over the doctor's back, digging fingers into the thick fabric of his jacket. Gaster hummed and pushed himself forward more firmly, bringing his other hand down from the wall to the back of Sans's head.

He could hardly form cohesive thoughts, his head was feeling warm and light, and the hallway around them spun with every breath. He grinned wide and brought his arms to the back of Gaster's neck to pull him closer, if closer were possible at this point.

But Gaster pulled back, just for a moment, to push Sans's head to the side and make a move for his neck instead, kissing each vertebra with an intent that made Sans's toes curl. He laughed and groaned and pressed his head back into the stone wall behind him. "It's gonna be a long walk back to the lab," he whispered, roughly.

"I know," Gaster whispered back, "plenty of time for us to talk."

"Oh, right." That was what he had forgotten. Gaster pulled back again, and his lustful, flushed expression settled into something more tender. He leaned in for another kiss, but stopped short, something down the hall catching his attention.

"Someone's coming," he said, looking back at Sans and draping his arms over the skeleton's shoulders, "are we going to get caught like this?"

Sans shook his head in an effort to clear it. "Let's get out of here."

Gaster stepped back, smoothed out his coat, and picked up the papers they had discarded on the floor, handing half to Sans. He straightened out the other half, and turned towards the sound of approaching footsteps around the corner, all while Sans was still catching his breath.

"Ah, perfect timing, Guard?" Gaster called, rounding the corner, "sorry to bother you-"

"Oh! Haha, I'm sorry, Doctor, you gave me a startle. How can I help you?" the guard replied.

Sans took a deep breath, straightened his papers, and followed. He hoped the flush wasn't still visible on his cheek bones. He recognized the guard talking to Gaster as he rounded the corner... Pango? It must have been Pango. Not many Pangolin-shaped monsters in the Underground. He waved to them as he approached and they nodded to him.

"Yep, there's a fusebox right down this way, next to one of those wall sconces. You must have walked right past it!" they said, pointing back over their shoulder, "Want me to take you to it?"

"No, no thank you." Gaster waved them off. "I'll let you get back to your rounds, sorry for interrupting you."

"Not a problem at all, Doctor, have a good day! You too... Sans? Sans."

"Yeah, take care, Pango." Sans replied, waving goodbye. He caught up with Gaster again and walked just behind him as they came up to a fusebox on the wall at the end of the hall.

Gaster opened the door to the fusebox, and immediately shut it again, without even looking inside. "All in order!" He grinned down at Sans. "Shall we?"

Sans chuckled, nervousness finally seeping out of him, as he returned to Gaster's side. "Those hearing aides must work leagues better than... whatever I've got, that was close."

The doctor perked up. "They work well, yes. How did you know?"

"Was I not supposed to? Alphys told me about all that a while back."

"No, that's fine." He looped his free arm around Sans's shoulder, and led him down yet another hallway. "I like to think they work well, anyways. There are some things I swear they don't pick up on, like the sound of my phone ringing."

"Don't you have it on silent?"

"Hmm, yes, that could be why. " He stopped walking suddenly and pulled his cellphone out of his pocket. "I had it set to vibrate today, though, in case you needed to reach me." He glanced at Sans pointedly as he returned the device to his pocket. "By the way..." Looking first to see that no one was around, he reached out and cupped Sans's jaw with his free hand, and leaned in for a slow, tender kiss to the side of his mouth. Sans shivered and closed his eyes. He felt a lump forming in a throat he didn't have. "Let's talk," he whispered.

"Sure." Sans let himself be herded once more toward the exit of the castle. "Okay, so I'm sorry I got snippy, and jealous, and you _probably_ don't deserve that. It won't happen again."

"Don't just say what you think I want to hear, Sans." Gaster sighed as they stepped out of the palace. "What's on your mind?"

"I don't know, really." Sans looked down. "I know it's stupid, but the way he looks at you... it's..." he trailed off. He hoped Gaster would say something to lead the conversation while he gathered his thoughts, but the doctor said nothing and they walked for several minutes in silence. "We're not even really a couple, are we?" he finally asked. "So, I have no say over what you... I mean we've been on a couple of dates, and we've slept together, but..." There was a squeezing in his ribcage that hurt like nothing else.

Gaster had turned to look at him with a very serious and sad expression. "I don't know what you mean by 'we're not a couple', you're the person I choose to spend my time with, and dating and sex are usually reserved for those who are romantically involved with one another. God, listen to me, I sound like a textbook."

Sans chuckled dryly "They aren't always reserved for... Well, I've fooled around with a lot of people and-" whoops. "I mean a _handful_ of people, and I've been on a few dates with some of them, but it wasn't like that gave me the right to tell them I didn't want them seeing anyone else. It's like that, we've just got something casual going, something under the radar, and I don't have any right to say-" He stopped, it was getting harder and harder to form the words he needed. Each one clung to the back of his mouth like it were coated in glue.

"To say what?"

Wow, were they getting close to Hotland? That must have been why Sans was feeling so warm and uncomfortable. "I don't want to see you with anyone else," he muttered, "because I like you and want to keep this going. We just started, and I'd hate to think I've rekindled the way you felt for an old flame."

Gaster pulled him closer. " **You** are the person I choose to spend my time with," he repeated. "Casual and secretive though it may be, due to the circumstances." His brow furrowed. "I cannot put aside my obligations to other people, Asgore included, but I can tell you that anything he still feels for me is not reciprocated. I care about him and his well-being very much, but there are so many reasons why I could _never_ go back to that. He's married, we're both busy all the time, there is a ridiculous age gap between us, and when it comes down to it, I can't take the pressure of trying to make sure he's happy." He sighed.

Sans looked away as heat rose to his cheeks. "Asgore **was**  married," he corrected, "he's a widower." He wasn't sure what else he could say to all that.

" **Regardless** , there's someone new in my life, and I'd like to see how that progresses. If you'd like it to be more than something casual, then perhaps, we should go on a few more dates, and see how things go." He stepped in closer to Sans, and the skeleton glanced up to see him looking as nervous as ever. "Because I think they could go well."

"Yeah, let's do that," Sans said quietly. His soul fluttered in his ribcage. "Maybe you should come over to my place some time, I've got a few _pie recipes_ you could try out."

Gaster looked down at him like he had just been shot. "Is that... you-"

"Oh look, we're almost to the lab."

* * *

The whole reason they had stopped at the lab was to drop off the paperwork with all the data and observations their team had gathered on the human souls earlier that day.

_Mission accomplished, at least_ , thought Gaster. The papers had been set down neatly on a desk just inside the door. But he and Sans hadn't made it much farther than that, and since there wasn't much in the way of furniture in the lobby...

There they were, in the middle of the floor. Sans was flat on his back, looking up at him with such bright pupils and a smile that had his heart beating rapidly. He was short of breath, though he did his best not to show it. He laced his fingers in between Sans's and kissed him on the cheek gently, as the skeleton wrapped his arms over Gaster's shoulders.

"This a date?" Sans whispered, close to Gaster's neck.

He shivered. "No, this isn't quite what I had in mind but..." His lips ghosted over Sans's jawline. They really should have at least gone somewhere else to continue their necking, but Gaster's self control and common sense rarely worked together these days, it seemed. "We can probably do something productive while we're here. In a moment. Or two."

"Something  _reproductive_ , maybe." Sans grinned wide at him.

Gaster snickered, then pulled back suddenly, alarmed. "That's not- we couldn't, could we? Can you...?" Things would get far too serious far too quickly if they actually managed to reproduce.

"Nah, skeleton's can't get pregnant, don't worry." Sans winked and pulled him closer.

"How do- _mnf_ " his question was cut off with a deep kiss. Gaster shrugged and let himself enjoy the moment. He was having fun with Sans, and if the thrill of doing something he shouldn't (with _someone_ he shouldn't, in _places_ he shouldn't) were to wear off, and something else were to take its place? That would be quite alright.

He was looking forward to it, actually.

* * *

 

An hour or two later, they had picked themselves up, straightened out their clothes, and made whatever preparations they could think of, before Gaster once again opened a doorway to the void.

He and Sans stood in front of the darkness, staring in silence, as they prepared to step in.

**Notes for the Chapter:**

> Next time on SYCM: the void stares back!
> 
> If you have further questions on skeleton reproduction... they'll get answered Later in the fic, when a certain someone makes an appearance.   
> Or you could ask me about it on the tubmlrlrlr, and I can give you some cannons shaped like my head.


	29. Unknown Territory

**Summary for the Chapter:**

> Blue skiddoo'd, and we can, too!

The room behind them blinked away as they stepped in, leaving only a razor-thin strip of light by which they could navigate in the void. Sans clung close to Gaster's side to avoid losing him, and Gaster moved forward slowly, feeling his surroundings rather than seeing them. They charted the darkness, step by cautious step. The weight of the void around them pressed in, dancing across Gaster's face and hands soothingly as he reached out.

  
“Does it just keep going forever?” Sans asked quietly. Or perhaps he asked normally and his voice was just muffled by the density of the air around them. Gaster could hardly hear the sound of his own footsteps. Through the base of his skull, he _could_ hear the sound of drifting particles. Sand running over itself, salt dissolving in water. .

  
“No,” he replied, “it's hard to tell, but I think it stops just ahead..” He pressed forward with his fingertips and felt the rippling pages of a book, layers of fabric, blades of grass that could be maneuvered through with enough force and finesse. “Never mind, it keeps going. There's a permeable field around us, I think. Hold onto me and I'll try to push through.”

  
Sans's grip tightened on the back of his sleeve, and with his other arm, he pushed through two layers of the field ahead and felt them shift around his hand, parting just enough for him to slip between them. After a few steps, he and Sans came out the other side... into more nothingness.

  
“Odd, I don't think we actually _went_ anywhere.” Gaster whispered, looking around him. He turned towards Sans, unable to see anything of the skeleton except for the glow of his pupils. The thin strip of light from the lab was still behind them, still just barely visible.

  
“Nah,” Sans said, clearly able to hear Gaster just fine, “There's something on the ground up ahead now.” He took hold of Gaster's wrist and pointed his arm off to the side.

  
There was indeed something up ahead, something long and writhing. Perhaps a little less dark than the rest of their surroundings, perhaps a little more so. It was definitely a **different** dark. But on the ground? It looked to be hovering in the air.

  
He walked forward slowly, pushing through several more layers of sheets and blades and layers before they were less than two yards from the something. Close enough now to tell that it was a trail of some sort, and that it was indeed above the level at which they were standing; sitting just about at the height of Sans's eyes, or Gaster's navel.

  
The trail blinked and shimmered, and after a moment of concentration, Gaster could make out individual prints, tiny and staggered against the dark of the void. “Paw prints,” he muttered, reaching out to touch one. It flickered and faded under his fingers. No doubt the small, annoying dog had left them. The trail was short and cut off suddenly, cutting one of the paw prints in half. He heard Sans shift beside him, and could see the faintest outline of the skeleton's hand as he waved it above, then just below the trail.

  
“Guess he's on an entirely different level,” Sans muttered.

  
Gaster hummed absently. “He left right around here... We should be able to as well.” He reached forward and felt another ripple in the dark. “But where would we end up?”

  
“Maybe the beach,” Sans suggested, taking hold of his wrist, “that's where I'd go.”

  
The gaps around Gaster's fingers shifted as he pushed forward, parting in an unexpected direction. As he and Sans pushed through and the static weight of the void released them, they were greeted with the smell of damp soil and the sound of lapping water.

  
“I don't- Are we in waterfall???” Gaster searched around quickly. In the high ceiling above them, scattered crystalline shards glowed and sparkled like colorful starlight. Behind them, tall grasses and blue flowers swayed despite the lack of wind. Ahead, the river that ran through most of the underground flowed past the dark shoreline. There was no trace around them of the void they had left behind.

  
“Can we get back the same way we got here?” Sans asked.

  
Wordlessly Gaster held his hand up at the riverbank and focused. Magic curled its way out of his palm, and evaporated into the air. “It's not working,” he whispered. He tried again, nothing.

  
A bubbly voice sprang up from down the river. “Do not worry, friends! I see you!” Sans and Gaster stepped back as an ornate wooden boat pulled up swiftly to the shoreline beside them. “Are you in need of a lift?” it asked. The cloaked figure on its back waved a hand in greeting.

  
Gaster glanced from the boat, to the figure, to Sans, unsure.

  
Sans shrugged and shook his head. “Sure, why not?” he asked, stepping forward. “Can you take us to the Hotland shore?” He took the cloaked figure's hand and stepped aboard the boat.

  
“I certainly can!” it chimed back happily.

  
“You coming, Doc?” asked Sans.

  
Gaster held his hands up in the air, gesturing behind himself. “Shouldn't I try to take us... back?”

  
“Let's figure it out back at the lab, yeah? You left a door open back there, and it might not be safe to do the same thing out here.” He winked.

  
“Yes... yes. You're right, let's go back and we'll figure it out there.” He followed Sans onto the boat cautiously, and sat down on the edge of its back. “Sorry for the delay,” he told the river-person.

  
“Don't worry at all, friends, just hold on and enjoy the ride!” It took off at a steady pace down the stream, picking up speed slowly as it headed toward Hotland.

  
Gaster sat back and enjoyed the shift in temperature, and the gentle sway of the boat as they traveled. He looked over to Sans, who had only one eye open and a lazy grin on his face. “What?” he asked the skeleton.

  
“Nothing,” Sans whispered, “it's just kind of nice.” He looked away, but Gaster saw his grin widen.

  
“Brace yourselves, friends, here we are!" the river-person called out as they approached Hotland's shore.

  
They thanked them as they stepped off the boat, then made their way quickly back to the lab.

  
“Okay, so what's our plan?” asked Sans as they stepped into the lobby. He picked up the stack of papers they had left there earlier, and tucked them under his arm.

  
“I'll try making another opening up here, and we'll see if we can get back to the lab proper from there,” Gaster stated.

  
“That'll just leave another enchantment for us to undo later, though.” Sans's brows knitted together as he thought. “Any way to make the enchantment temporary? That way it could close up on its own?”

  
Gaster groaned for several long seconds. “I suppose it's worth a try.” He held out his hand again and focused his magic on the air in front of him. It dissipated. “Hmm.” He made a second attempt. Nothing. “I'll be furious if this was all a fluke that only worked on one doorway,” he growled as he readied his magic for a third try.

  
“Hold on, you're not actually casting it on anything,” Sans reminded him, “You said it opens up space between things, but we only got into that space because you used it on a door. Maybe that's why it's not working up here.”

  
“...That... alright, yes, that makes sense. So what we need is...” he trailed off, looking around. Better not cast anything on the elevator, lest he accidentally screw up the whole thing. His eyes fell upon the seldom-used back door to the lab. “that door!” he concluded. They marched over and Gaster's enchantment took hold immediately this time, as they pushed the door open. “In we go, quickly!”

  
Once again they entered the void, this time with a thin sliver of light on either side of them. They watched as the one they entered through slowly shrunk until it was gone, leaving them with only one. They pushed their way quickly toward the remaining strip of light. Reaching through it, they made their way back out to the lab proper.

  
Sans heaved a sigh of relief as they stepped out, and nearly tripped over the tiny mass of fluff that was waiting for them on the other side.

  
Gaster reared back immediately at the sight of the dog, whose tail was wagging excitedly at their arrival. It gave a tiny 'yip' and slipped past them, into the darkness behind them. He turned and closed the enchantment immediately after it, with a snap of his fingers.

  
“You're getting pretty good at that,” said Sans.

  
“Thank you.” Gaster replied with a proud smirk. He didn't know for sure whether Sans was referring to his magic, or the way he dealt with the pesky dog, but decided it might as well be both. He sighed and rubbed the back of his neck, which was still prickling from the constant tinkling, thrumming, enveloping sound of the void. Tiny particles and fragments of _something_ he couldn't pinpoint were moving about in there, he was sure of it. He would explore it more thoroughly later, he decided. “Why don't we sit down for a bit and take notes?” he suggested.

* * *

  
They wrote down everything they experienced while in the void, every sight, sound, sensation, then compared notes to see what matched up. Sans couldn't hear any drifting particles or moving sand, but could hear everything else just fine while they were in there. He could also feel the rippling layers of something as they pushed through. They both admitted to feeling a little drained by the experience, but it had been a long, eventful day.

  
It would be best, they both agreed, to wait a few days before going back in.

  
“So, since we both need to take a break, would you like to come over for dinner some time?” Sans asked, as they were getting ready to leave the lab.

  
“You can cook?” Gaster asked, one brow raised.

  
“I learned a few things in college, yeah.” Sans grinned. “My apartment's tiny, but there'd be enough room for the two of us in there.”

  
“I'd love to, then. Let me know when you'd like me over.”

  
“How about tomorrow night?”

  
Gaster stopped to think for a moment. “Sure,” he decided, “it's a date.”

  
Just outside the lab, on his way home, Sans realized he had no idea what to make for them.


	30. Steamed Hams

**Summary for the Chapter:**

> Here comes drama.

"Gaster? You're a bit early," said Sans through the partially open door. "Dinner's not quite ready yet, I'm still cutting the shallots, and..."

Gaster stood before him timidly, clutching a glass bottle with both hands. "I was hoping I could keep you company while you cooked, if that's alright?" he asked.

"Heh, come on in, it's not like I'm going to turn you away." Sans stepped back and held the door open as Gaster entered his apartment for the first time, then shut it behind them gently. "Welcome to... my place. Like I said, it's pretty cramped, but there're a couple of chairs and I figure we could..." He fell silent as he watched Gaster look around his apartment, taking everything in. Gaster's eyes hung over the bed just a moment too long before he turned to Sans with a smile, as if he didn't think Sans would notice.

"We could... what?" Gaster prompted him.

"Oh, um, we could use the desk as a sort of table, if that's alright?"

"Quite alright with me, yes," he said gently. "Oh, by the way, I brought this for you," he held up the glass bottle he had been carrying. "Sparkling water. You don't have to use it tonight, or ever, I guess, but... well, here." He offered it to Sans who took it gladly.

"Thank you. And, I mean, it'd go great with dinner tonight, it's perfect. Thanks." His natural grin spread further across his face as he accepted the gift.

"Right, what are you making, if I may ask?"

"Steamed clams," Sans said proudly, "Family recipe, from one of my friends from college."

"So-"

"Not my family, his," he corrected himself, "No good cooks left in my family."

"Not even you?" Gaster asked, grinning.

"Guess you're about to find out, huh?" Sans replied with a wink.

Gaster hummed skeptically while Sans pulled one of the chairs closer to the kitchen counter for him. He took a seat and Sans returned to cutting shallots, carefully.

Sans wasn't worried about cutting himself so much as embarrassing himself in front of Gaster. It was worth it to take his time for this. He picked up the cutting board and brought them over to the lidded pan on his stove, which by now was definitely heated up. He slid them in slowly, and stirred them around a moment before returning the lid. As he turned around, he found Gaster watching him, studying him intently. He held eye contact with the doctor as he turned to wash his hands, and watched as a faint blush crept across the doctor's face.

"Is there um, anything I can do to help?" Gaster asked, twiddling his fingers.

"Do you know how to wash clams?"

" _Welllll_ , no. No, I do not."

"I'll show you." Sans grabbed a large bowl from his icebox and placed it in the bottom of the sink, motioning Gaster over. "I've had these soaking in saltwater for a couple of hours now, to purge the sand- and whatever else is in Waterfall- out of them." He turned on the faucet, picked up a handful of clams, and held them under the flow, turning them over and rubbing their shells, before setting them on a towel on the counter next to him. "Just like that, see?"

"Simple enough," said Gaster, mimicking what he had seen. He took over washing the rest of the clams while Sans stirred the shallots on the stove. "Alright, what now?" he asked, turning off the tap after all the clams were clean.

"Just a second here, and I'll put them in the pot", he said, setting the lid aside. Gaster passed him the towel full of clams, and he carefully slid them into the simmering pot. He spread them around gingerly with his spoon, and quickly replaced the lid. "Alright, now we wait, and they'll pop open when they're ready to be eaten. Takes about.. ten minutes?" said Sans, casting a quick glance to the clock hanging on the wall.

Gaster looked at him expectantly.

"Means we've got ten minutes to kill, I guess. Doing whatever. Since you got here early and all." He began backing the doctor up against the kitchen counter, a sly grin spread across his face.

"Ten whole minutes, hm? I can work with that." Gaster leaned down to meet Sans in a kiss.

Sans slid his leg between Gaster's legs.

Two loud knocks sounded against the door.

Gaster pulled back, startled. "Are you expecting company?" he asked quietly.

"No, just you. Keep an eye on the clams for me? It's probably my brother."

The doctor nodded, practically pouting, as Sans stepped away to answer the door.

He pulled it open just a smidge, poking his head out. "Hello?"

"Sansy, sweetie! Did you get my text? I just wanted to stop by and drop these off, but I've got a favor to ask you, so I guess I'm here on business."

"Oh." Sans glanced quickly at the paper bag being held out to him, then back up at his visitor, a short, thin, frail skeleton. "Hi, Mom."

He heard something clatter to the floor behind him, and winced.

"May I come in?" Verdana asked, her free hand planted on her hip. It was less of a question, more of an expectation. She must not have heard the clatter inside the apartment. Sans pulled the door a little further closed around his shoulders.

"I would love that, mom, really I would, but I'm um, not feeling the best right now, and I'd hate for you to catch whatever it is." He could feel sweat beading on his forehead, and could smell... pepper? Why was he smelling pepper?

Gaster sneezed behind him, too loudly. He flinched.

Verdana cocked a brow, an understanding smile spread wide across her face. "Oh, you've got someone over," she cooed.

"Haha, no, I just-" he flinched as Gaster sneezed again.

Verdana chuckled. "He sounds handsome."

"Mom."

"Can I meet him? I promise, I won't embarrass you," she said with a dramatic wink.

" _Mom_ , I'd really rather you didn't right now, if that's okay."

"Oh, I suppose if neither of you are **d e c e n t** , I could come back later?"

"What? It's not like that, we're just cooking dinner!"

She tilted her head to the side. "Then what's the problem? Papyrus did mention something about you seeing someone, if that's true, I'd at least like to say hi."

Sans hoped she couldn't hear the orchestra of screams that was playing inside his head. He and Papyrus were going to have a talk later, that was for sure. He felt a desperate tapping on his back. "Just, just a moment, ok? Please?" He quickly ducked back into his apartment, pulling the door shut behind him as he turned around.

The magical hand that had been tapping at his back dissipated. Gaster was kneeling down on the floor, with one hand over his face, trying to sweep up the pepper he had knocked over.

"What's wrong, you ok?" he asked in a hurried whisper.

Gaster began signing something, then sighed and shook his hands out. "The clams have started opening, I just thought you should- I'm sorry, this is the worst possible- Just _please_ don't tell her I'm here."

"What? it's only been like, four minutes. Oh shit." Sans looked over to the stove, the heat was set much higher than it shold have been. He rushed over to turn it down, and lifted the lid to move the opened clams out. A large billow of steam rushed out to greet him, throwing itself across his face and neck eagerly. It found its way almost instantly into his eye sockets and nasal cavity, and he reeled back in pain, dropping the lid back on the pot as he cried out.

The expletive had barely left his mouth when the door flew open behind him, and Verdana rushed into the doorway. "Sans, are you okay?" she asked. Sans heard the bag of treats she'd brought drop to the floor. He turned to her and lifted his hand from his sockets to find her silent and staring, not at him, but the monster next to him.

Sans recognized the expression she held, not just her face, but her whole posture; fists clenched, shoulders back, spine as erect as possible to make even her short stature seem intimidating, and feet close together, with one pointed towards the target and one in the direction she'd like to throw them. Sans had, of course, seen it in scattered intervals throughout his whole life.

Someone was in trouble.

To his surprise, however, she actually raised her voice at them.

"You, _**DINGUS**_ ," she growled loudly, her deep voice coating the room around them.

Gaster stood up quickly, ramrod straight. "Don't call me that!" he shouted back at her.

"I'll call you whatever the hell I want to call you! After everything, all the _shit_ you pulled with my wife, you go after my SON? Who the hell do you think you are?!"

"What?" a whisper in stereo, from both Sans and Gaster.

"You're Mollig's son?" Gaster asked in a pained whisper. Sans looked over to find him staring with a look of concentration

"You really didn't know?" Verdana crossed her arms.

"I... I see it now that I'm looking for it, I guess. I should have figured the two of you... Oh my god." He placed his hand to his forehead, turning away from the both of them. "Ohhhh my god."

Sans had no idea what was going on. "You knew Mollig, too?"

"We were friends, a _long_ time ago."

"Emphasis on _were_ ," Verdana interjected, " **Get out**."

" **Mom**." Sans reached over and turned off the stove. "You can't tell people to get out of my apartment."

Her eyes flicked between the two of them rapidly. "Fine," she sighed. "I'll go, I need to take a walk. When I get back," she pointed at Sans, "We're talking about this."

Sans shivered.

" _You_ ," she continued, pointing at Gaster, "talk to him while I'm gone. Tell him what you did, what an _ass_ you've been. If you're fooling around with an employee half your age and you have history with his parents? You tell him. _Everything_. Because apparently he knew just enough to not tell me anything, and that's not okay." Without another word, she turned on her heel and left, shutting the door carefully behind her.

The small apartment felt stuffier than it had earlier that evening, even with only the two of them there. Sans slumped back against the counter, sighing. "Well, that was something," he mumbled, his tone overly-casual. His knees felt weak, achy. "You okay?"

Gaster continued to stare at the door. "I really had no idea, this whole time. You never mentioned Mollig as your mother."

"Yeah, I don't mention her much to anyone." Sans looked down at the pot of clams, which were probably ruined. "She's the one who gave birth to Paps and me... She's been gone about six years now." He watched Gaster hunch in on himself. "Do you wanna tell me what all that was about? What happened?"

"I was cruel to her, when I knew her. Verdana too, by extension. We were friends once, and then I got upset at her, jealous over something petty, and I... I turned on her. God, it was so long ago, I don't even remember what started it all."

Sans chuckled dryly. "Ain't that just the way?"

"I bullied her relentlessly, for the rest of our school days, and it would have continued past that, I'm sure, if Verdana hadn't put a stop to it. I can't believe they got married. And had... you."

Sans felt small, suddenly, watching Gaster look him over, probably searching his features for echoes of the two of them. He knew right where he fell, having taken after Verdana's skeletal appearance, the only other way he resembled her after that was her height. The rest was all Mollig. He watched Gaster's expression though, as the knowledge dawned on him for the first time, and he looked away.

"Was it really that bad?" Sans asked.

"I didn't think so at the time, but I probably made her life hell. I used to slip notes into her locker and bag, when she wasn't looking. Little, discouraging things. I told her she'd never get the scholarship she was after, once, and then later found out she'd rescinded her application for it. "

"She never mentioned you, though. Neither of them did," Sans assured him. "Not that they ever talked about their past much, but even when I talked about you as a kid, and wanting to work on the Core, neither said anything against you. I mean, it can't have been that bad."

"It was bad enough that Verdana hasn't forgiven me, after all these years. Are you really defending me right now? After I was a horrible bully to one- no, to _both_ of your mothers?"

"I... I don't know." Sans could feel himself blushing, golly, he was doing that a lot these days. But this was a different kind of embarrassment, not good. "I mean, you haven't been like that as long as I've known you."

"But I was."

"But you aren't, now. I get that you were an asshole to my parents. That was real shitty of you. But for the... admittedly short... time that I've known you, you haven't been like that. Not to me."

"I'd like to think I've grown up a bit since then," said Gaster with a wry smile, "A bit." he repeated. "Look, you should talk to Verdana about this, see what she has to say. And I should... I should get going." He slumped a little. "I'll have my phone on, if you want to talk to me..." He waved his hands as if to continue the sentence, but stopped talking, leaving the expression as is. "If not, I'll see you at work on Monday."

Sans reached out for the back of Gaster's shoulder, before he could get out the door. "I'm sorry about dinner, about all of this," he whispered.

Gaster thought for a moment, then leaned down to give Sans a quick peck on the forehead. "Don't be sorry, this whole thing was basically my fault."

**Notes for the Chapter:**

> I went to /ck/ to ask them what I should make if I was having my boss over this weekend, and wanted to impress him. The only response I got was "steamed hams."  
> Steamed clams it was, then! I had to look up a dessert pairing on my own, and most sites recommended something a bit on the salty side for dessert, since clams have kind of a sweet flavor.   
> Salty... like tears? ;'-3c  
> Yeah, that sounds good.


	31. Serious

**Summary for the Chapter:**

> Heyo, here's your warning that there's gonna be some insecurity (and a bit of panic) in this chapter, but not from Sans. This time, it's on Gaster.

Gaster shambled back to his house slowly, listening intently for any noise from his cellphone. Every five minutes or so, he would stop walking and check to make sure he did in fact have the volume for his ringer turned on. Each time, he would drop the phone back in his pocket with a worried sigh.

 _It's probably going to be a while before Sans gets back to me_ , he thought. _If he gets back to me at all._ He reached his own front door without realizing he was even near his house. He stepped inside, quietly slipped off his shoes, and began to pace frantically across the living room floor as a kind of panic set in.

"Oh god," he whispered, "this is it, isn't it?" There was no one in the house to answer him. His hands were flying through the air as he spoke, vaguely translating his emotions into something anyone spectating would have barely understood as words. "It's all my fault, this is my past finally catching up to me, getting back at me for all the damage I've caused over the years, what a-a- a _TROUT_ I was to everyone." He couldn't really remember what a trout was, but it sounded severe enough to sum up his attitude and ego and rude actions. "He's not going to talk to me after this, let alone _date_ me!" Not that Sans's inevitable anger at the situation would be unjustified. Gaster would understand completely.

"He... We were..." he trailed off, his hands continued moving, imparting his thoughts to the empty air. We had just spoken yesterday about the possibility of a serious relationship, and FOR WHAT?!" He turned and smacked the flat of his back against a wall. _No_ , he realized, _it's better this way, better that it ended before things got serious. It's good that I didn't have time to get attached I..._ His hands stilled. Wasn't he already kind of attached to Sans? _No_ , he assured himself, _I wasn't any more invested in him than Dr. Larkeet, or Alphys. Monsters that I've... known for years... Oh god, no._

Gaster allowed himself a few dry, quiet sobs. He'd give Sans a couple days off, time away from work to think, if he needed it. If Sans didn't take them, Gaster might do it himself. A couple days for the awkwardness of a failed workplace relationship to ebb away would make things easier for both of them. He took a deep breath, then two more. Things were going to be okay. As Sans's employer he would of course need to show grace and discretion and be professional about all of this. He would show Sans that he wouldn't need to fear for his job, because if he began to fear for his job, he might become uncomfortable and leave the lab, and Gaster would probably never see him again.

He picked himself up slowly from the floor and made his way to the kitchen, still rather hungry from the promise of dinner not an hour ago. He made himself a quick meal with what stale ingredients he already possessed (nothing fancy or romantic, like what Sans had planned for them) and flopped down on his couch with a book he had read many times before about the history of salt.

* * *

  
"You cooled down any?" Sans asked, opening the door halfway to greet his mother.

Verdana took a deep breath, held it, and let it go. "I think so," she responded.

He backed up and held it open as she stepped into his apartment, then shut it behind her gently.

"I'm sorry I blew up at you," she said, almost immediately.

"Really?"

"Really. I'm still kind of hoping this whole thing was a misunderstanding and that my anger was completely unjustified..."

Sans's face bloomed in embarrassment. "No, I invited him here on a date. We're kind of doing that, dating."

Her eyes narrowed. "Is he forcing you into this? If he is, we can talk to King Dreemurr, because that's not- not okay in the slightest, and if I find out he's been taking advantage of you, or blackmailing you-"

"He's not!" Sans cut in, holding his hands up. "Mom, I started this, don't worry."

"You don't have to continue it, sweetheart."

He sighed, exasperated. "It's really, _really_ not like that, it's not even anything serious." He made his way over to the pot of clams and began scooping them out into a bowl. "I'm gonna need you to help me eat these, by the way."

She stared at him with a skeptical expression. "He's not a good person, Sans. Did he tell you _anything_ while I was gone?"

"Yeah, he did. I can see why you don't like him." Sans grinned in spite of himself.

"He was _horrible_ to Moll. They were best friends for so long and he turned on her like it was nothing. She never forgave him, either. All those years and he never came to apologize."

"Are you going to tell me not to date him?"

She sighed, laughed, and rubbed one palm over her face. "You're an adult, Sans. I can't really tell you what to do any more. I have to trust you to make your own decisions." The words rolled off as if they were practiced, and being recited. "Your own mistakes, too," she added, picking up a clam. "Gosh, I was waiting for the day I'd catch you with one of your teachers or something, but this blew me out of the water."

"Heh. Thought about it once or twice."

She shot him a stern glance. "These clams are delicious," she muttered.  
  
He shook his head. "Nah, they're overdone. Gaster and I are trying to keep this whole mess quiet, by the way. So... I promise I won't bring him home for dinner, if you promise not to blast it all over the news?"

"Oh no, I forgot! That was the whole damn reason I showed up here in the first place. Fuck!"

Sans stared at her quietly, waiting for her to say more.

"I didn't want to go through him directly, but I was going to ask you to get me an interview with Gaster or one of your colleagues," she said as she leaned forward and gently thunked her head against the desk, "so I could do a report on that new project I heard you're working on, a cannon or something? Way to go, Verdie, way to muck that up."

Sans snorted and almost choked on a slice of shallot. "Wow, Mom. He's sure to give you an interview now."

She groaned against the wood of the desk.

"You know, I've got an in with that guy, I'm sure I could find a way to **convince** him to give you a second chance." He winked at her even though she couldn't see his face.

"Sansy, I do not want to be hearing that, or any details about your illicit relationship with your boss, for that matter," she grumbled, "I'm getting too old, too brittle for all this."

"Got it, I won't come crying to you if things don't work out."

"I never said that!" She jerked her head up from the desk. "If he hurts you and you want him to face hell, you come to me right away. I will be there for you, Sans."

"Thanks, Mom," he said, smiling softly. He really hoped that would never be the case, but if it did come to that, at least someone would be on his side. "How about you take the rest of these clams home to Paps for me? I gotta go see if I can... getcha that interview." He stood up from his chair and headed to the kitchen to grab some foil.

"I'm sorry for ruining your date, sweetheart," said Verdana as he wrapped up the bowl. She looked like she actually meant it.

"It's fine," he replied, giving her a quick hug, "with any luck, there'll be more to make up for this one."

He bid her goodbye, and slumped with his back against the door as he formed a plan. Tonight could still be salvaged, he knew. He still had dessert waiting in the icebox, and the bottle of sparkling water Gaster had brought him. They could probably make do with that. He bundled them up together, and took a quick look at the clock.

 _Not good_ , it was way later than he had planned, and asking Gaster to make his way back to Sans's apartment after that whole big scene was out of the question. It would take Sans the same amount of time to just walk to Gaster's anyways. Unless he could take some sort of shortcut.

Now there was an idea.

Sans thanked his stars that his magic was the way it was. He had no specialty or affinity of his own (just the bones that his mother and brother also used), but he could mimic other monsters' magic like nobody's business, and _make_ it his own.

He approached his closet cautiously and focused on recreating Gaster's enchantment, the temporary one that would close up behind him when he stepped through. At first he was afraid it wouldn't work, but he closed his eyes tightly and after a few moments, could feel the spell tugging gently on the tips of his phalanges. He opened his eyes, then the closet door, and stared triumphantly into the void.

Pulling out his cell phone and picking up the bundle of goodies, he waited anxiously for four rings before Gaster picked up on the other line.

"H-hello?" Gaster's voice sounded kind of... crumbly.

"Hey, Doc. It's me," Sans replied, "You at home?"

"Oh, um, yes. Yes I am, I was just," Sans heard the rustling of paper, "Catching up on some reading. A good book. Very. Informative."

"Cool. Is it alright if I come over?" he asked, hopping into the void before the doorway could close up on him.

He was answered with garbled static. Puzzled, he pulled his phone away from the side of his head. His screen was binking on and off, and the call timer kept resetting back to zero. He took a shaky look at the darkness around him, suddenly a little worried. The sliver of light marking the point where he had entered closed up as he looked over to it. If he couldn't make his way out like he had thought, he'd be screwed with no way back. He hung up the phone and slid it back into his pocket while he looked around for the right exit.

He reached forward and could feel those waving layers of _something_ parting at his touch like reeds. That was how Gaster had gotten them out before, right? By pushing through those? If he was right, (wow, he really hoped he was right about this. the pressure in this black space was intense) they should open up to a variety of places. He leafed through until he found a space between two layers that just kind of... felt like it would lead him to Gaster, and slid through, keeping his other arm and the bundle in it pressed close to his chest as he felt his way through with his leading hand.

The space seemed to open up, but suddenly there was something hard and flat in the way.

 _A wall?_ Would he have to turn back?

He slid his palm down the surface, until he felt something jutting out near his waist. A knob. A door knob. He grasped and turned it, and the door opened.

Suddenly he found himself in a familiar living room, with a surprised Gaster staring at him, still clutching his cellphone tightly near his face. Sans glanced behind himself, but the doorway showed no evidence of how he had actually come through. He looked back at Gaster, and shut the door behind himself slowly. His little shortcut had worked just fine.

* * *

 

Gaster stared at Sans, who had called him, hung up, and come through his front door without knocking. He held his breath, hoping for some explanation as to why Sans was there, but also bracing himself for bad news. The skeleton was clutching something tightly to his chest.

"Sorry, I uh, should have knocked," Sans mumbled, slipping off his shoes. He looked up and gave Gaster a lopsided grin when he caught him staring at the bundle in his arm. "Are you still hungry? The clams were ruined, but I brought dessert."

"Dessert?" Gaster repeated.

"Yeah." Sans slowly closed the distance between them, and set the bundle down on the arm of the couch. "I was hoping we could continue our date? I'm real sorry about the interruption, the commotion, and all that jazz."

Gaster began breathing again. "You spoke with Verdana?" he asked, quietly, lacing and unlacing his fingers nervously.

"I did," Sans replied with a shrug, "You okay there?"

"And you're still here... to finish our date?"

"Yeah."

He found himself shaking, just slightly. "You'd be perfectly within your rights to call this whole thing off," he recited, "I would understand, of course."

Sans's eyebrows came together slowly. "Do **you** want to call it off?"

Gaster held his breath again, and turned his face away. "No," he admitted after what felt like too long, "no, I really don't." He turned back to look at Sans, and found him smiling in a way that made his heart jump. His face began to grow uncomfortably warm. He reached out slowly with both hands, and grabbed Sans gently by the shoulders. When the young skeleton made no move to wrench himself away, Gaster pulled him slowly forward into a tight embrace. Sans's arms wrapped around his waist and he sighed in relief as they held each other close.

"You ok, Gaster?" Sans asked again.

Gaster pulled reluctantly away and nodded, smiling. "I'm hungry," he realized, suddenly. "What um, what did you bring for dessert?"

"An blueberry caramel tart, you're gonna love it," Sans said with a grin.

A few minutes later and they were sat together on Gaster's couch, enjoying (truly enjoying) the sweet and salty dessert while they talked. Sans decided to explain how he had gotten to Gaster's house so quickly, (Gaster had scolded him for taking such a risk) and he also mentioned the interview Verdana had planned on asking for before the whole fiasco happened. Gaster had laughed loudly at that, but nearly choked on his drink when Sans spoke of the things he'd be willing to do to secure that interview. He quickly changed the subject, and eventually they found themselves talking about Mollig, and how Gaster had treated her, and why Sans was still sticking around.

"... and I'm not saying it wasn't really shitty of you, but I'm not going to hold it against you if it happened that long ago," Sans explained, when Gaster pressed him further. "I mean, I'll keep it in mind, but you're a different person now, I think."

"I'm still the same person," Gaster corrected him, "I've learned many things in these past few decades, but I have still been me the whole time."

Sans nodded his head from side to side. "Okay, but if nothing else, statements like that prove you've matured at least a little since then."

"A little," Gaster agreed.

"Anyways, I still like you, even if I can't bring you home to meet my folks." He shrugged and chomped down on another forkfull of tart.

"I like you too." Gaster leaned in close and kissed Sans on the cheek, smiling as he watched the blush spreading across the skeleton's entire face.

He was grateful all his worrying from earlier had been for nothing, that Sans was still with him, both in the sense of keeping him company, and choosing to keep things going between them. He was so happy that his chest began to hurt, and he wasn't even sure how the hell to express it. He laced his fingers around the phalanges of Sans's free hand, and squeezed tight as he took another bite of the tart.

Sans scooted closer, to him on the couch, and looked him in the eye with such a sincere, tender expression that Gaster could feel everything within himself fluttering about. Things had changed just a little between them, he realized. They had formed a relationship, and like Sans, he wasn't willing to let go just yet.

**Notes for the Chapter:**

> Next chapter's gonna be a ~saucy~ chapter, buckle your seatbelts.


	32. Blueberry Pie

**Summary for the Chapter:**

> This is an explicit chapter, with sex. So if you're not into that, go ahead and skip this. Next chapter should be up before the weekend's over.

Sans had let Gaster undress him, though it would have been faster had he done it himself. Clothing is much harder to take off if you're being distracted with kisses and heavy petting. He had watched intently as Gaster undressed himself, too, their eyes locked as Sans sat shaking and eager on the bed.

Soon enough, he was straddled over the doctor's chest, bracing his hands on his femurs as Gaster slowly and cautiously stroked the lips of his freshly conjured vagina.

"You ever uh, p-played with one of these?" Sans asked. He had formed one at Gaster's request, but the cautious way he was being touched made him wonder if perhaps the doctor was unfamiliar with the anatomy. The slow, curious strokes of Gaster's fingers felt good all the same, and Sans had to fight to keep his voice down, his breathing steady. He rolled his head back as two of Gaster's fingers circled his clit.

"None of the men I've been with have had one," Gaster replied, as he dragged his fingers back down the outer labia. He looked up at Sans to watch his reaction. "Although one did have a cloaca, is that-"

"Heh, that's not the same thing. Not even close." He gasped and looked down as Gaster pressed his thumb into his clit. "That's not- _hnnnn_! Not a button, by the way," he whined.

Gaster smirked. "My apologies. I love the reaction it gets from you, though." He pulled his hand away and beckoned Sans forward with one finger. "Come here so I can taste you?"

"Yeah, sure," said Sans, his face heating up. He slid forward with Gaster's hands on his back, guiding him into place. He stopped just over Gaster's mouth and struggled to keep himself up with shaking knees. "This okay?" he asked.

The doctor nodded and guided Sans down gently. He stuck his tongue out and licked a slow, wide stripe up Sans's pussy. The quiet whimper Sans gave him seemed to urge him on, and he licked again, more slowly and firmly, before bringing his lips to Sans's wet, phantom lips and sucking gently.

Sans groaned and brought one hand to his mouth, shoving his knuckles between his teeth to try and quiet his moans.

Gaster pulled away to look him in the eye, smiling. "Don't hold back on my account," he whispered. Using his fingers to gently spread Sans's lips apart, he put his tongue back directly onto Sans's clit and gave it a few soft licks as he ran his hands up and down the skeleton's femurs.

Sans placed his hands flat on the wall in front of him, which was all he could do to keep from falling over. He rocked his hips forward gently, straining to resist the urge to buck forward into Gaster's mouth. He sure did let out a whole string of noises when Gaster's tongue slid into his entrance, probably none of them coherent. Every now and then he would hear Gaster let out a pleased noise of his own, a low hum of amusement at Sans's reactions.  
  
It became too much when the doctor slid his tongue out and started sucking on his clit. " _Woah,_  shit, s-stop!" Sans cried out, pulling up and away from Gaster's mouth.

"Are you alright?" Gaster asked, pulling back. "Sans?"

Sans took a moment to catch his breath. "Yeah," he panted, "I'm okay, I just. That was too much, I was gonna... gonna come."

Gaster chuckled and rolled his eyes. "And we wouldn't want that, would we?" he asked playfully.

"I mean it, though. _Wow_." Sans brought one leg behind him and rolled off of Gaster, slumping against the wall beside him. He was hardly surprised to look down and find the doctor sporting a raging erection. Another pang of arousal hit him at the sight, and he brought his own fingers down to lazily play with himself. He saw Gaster's cock twitch, and a bead of precum dribble from the head. "Wanna just fuck me?" he asked, turning to look at the doctor's face.

Gaster rolled onto his side and continued to watch Sans, entranced. "I think," he responded after a moment, "that 'fuck' is too strong of a word for what I want to do to you right now. Lie down on your back and get comfortable, please."

Sans chuckled, scooting down the bed till he was flat on his back. "Too strong a word, huh? how about 'let's have sex', or 'let us engage in vaginal intercourse'? Those any better?" Sans's eyes were drawn down to Gaster's hard cock again as Gaster got situated above him. "Let's do it," he whispered, bringing his gaze up to Gaster's half-lidded eyes.

Propping himself up on one arm, Gaster reached down with his free hand and guided the head of his prick to Sans's entrance. Once he was in place, he brought his hand up and cupped the back of Sans's skull, leaning down for a kiss as he slowly slid himself in.

Sans drew in breath after shaky breath as Gaster drove in deep, wrapping himself around the skeleton. The doctor took his time, kissing Sans and moving his hips; each thrust was slow, agonizingly slow, as he pulled himself out halfway before sliding back in to the hilt. He poured little noises of pleasure into Sans's mouth; gasps and grunts and moans with every stroke as he slid his tongue around. Sans was being filled with Gaster, wrapped in Gaster, and breathing nothing but Gaster. He slid his arms down and his legs up to wrap around the doctor in turn, to pull him closer still, and his breath hitched as the cock inside him throbbed.

They pulled out of their kiss, but not far. "Can I come inside of you?" Gaster whispered.

"Yeah, yes. Please?" said Sans, nodding. He brought his teeth to Gaster's neck, and peppered it with gentle nips and licks. When Gaster moaned this time, low in his throat, Sans could feel the vibrations on his tongue.

The doctor brought his mouth back down to Sans's, kissing him eagerly, and grinding into him even harder than before, though he did not speed up. At the end of every inward thrust, he gave an extra little push, as if he could get in deeper if he just tried.

It was all too much for Sans. He gripped Gaster tightly as his orgasm hit him, as if he were afraid of being washed away by the waves of pleasure that struck him. By the time they had stopped crashing over him, Gaster's hips had stilled almost completely, though his body was trembling, and he could feel the doctor's cock twitching inside of him. Gaster spilled himself drop by drop into Sans as they held each other close.

They parted from their kiss once more, and stayed like that for a while, arms wrapped around each other, before Gaster slipped himself out and sat up on his knees. Sans laid there for another moment, panting still, feeling something he couldn't place. He let his magic dissipate, and sat up as well.

"I think I need a shower," said Gaster, with a flushed face, "would you um, would you care to join me?"

"Yeah," Sans replied, softly. Words were probably not going to come easy to him for a while, he still felt dizzy and drunk off the afterglow of something he was still trying to piece together.

 

**Notes for the Chapter:**

> I believe it was GorrillazObsessor who mentioned that they'd 'love to see Sans ride Gaster with an ectovag' I took some time to think about it, and decided I agreed.(thank) Was face-riding acceptable?
> 
>  
> 
>  
> 
> Sidenote... I think I just got proposed to. Pretty sure I'm engaged, weird, huh? I can relate to Sans's joyous dizziness that much more now. :'-3c


	33. Listen to your mother.

**Notes for the Chapter:**

> For those of you who skipped the last chapter?  
> There wasn't anything I'd really consider plot relevant. I revealed that Gaster's been with more men than just Asgore, wayyyyyy back when. That's not really important.
> 
> There is just a tiny detail from chapter 31 that I tried to emphasize, and it's that Sans and Gaster are both feeling a little different about each other. A good different. A soft different.

Showering with another person was something new to Gaster, and he enjoyed the pure intimacy of it. Sans was more than happy to scrub his back for him, and they both laughed when he hopped out of the shower, slipped on the wet tile ,and nearly injured himself while trying to grab a scrub-brush for Sans's spine. It was all fun, helping each other get clean, but they were both very tired, and the shower couldn't last long.

As soon as they could be considered clean, they stepped out, dried themselves off. and made a beeline for Gaster's bed. In no time, Sans had fallen asleep, and Gaster smiled as he pulled the skeleton a little closer, and drifted off himself.

Because it was the weekend, they were in no rush to wake up the next morning, and it was nearing noon by the time they got out of bed to get properly dressed

"Soooo," Sans began, slipping his socks back on, "got any plans for the day?"

Gaster looked up from the top button of his shirt. "I might go down to the radio station actually, give Verdana that interview she wanted."

"Y'wha?"

"Yes, well. I think you've earned it." He smiled as he made his way down the rest of his buttons. "Just don't expect to get your way all the time by bribing me with various tarts and _bivalves_ ," he added with a wink.

"Oh my god." Sans flopped back onto the bed and Gaster chuckled. "Breakfast?" he asked, "what do you want to do for breakfast?"

"How about porridge?"

After breakfast, Sans offered to show him what he meant by taking a shortcut through the void space. Gaster insisted on walking to the station the old fashioned way. Not that he didn't believe Sans, but he didn't want to be taking unnecessary risks, either. He reasoned they could examine that possibility more closely from the safety of the laboratory, and implementing the buddy system to cut down on risk.

"Sounds good to me," said Sans, nuzzling Gaster on the cheek, "Good luck with your interview, lemme know how it goes." And with that, he walked over to Gaster's hallway and vanished.

"Sans!" Gaster shouted after him, much too late, " **what** did I just say?!"

He had plenty of time to think on his walk (you hear that, Sans? **Walk!** ) to the station in New Home. And on that walk, he decided he wasn't afraid of meeting with Verdana. It would be nice to get some information out to the public about their plans for breaking down the barrier, and if she had anything to say about her son and him being together, she could just say it. He was feeling warm, and confident, and ready for anything.

Of course, his mindset change once she was actually in front of him.

"Something you need?" she asked curtly, folding her arms tightly in front of her. She had maintained her short stature over the years since he'd seen her, but was no less intimidating now than at any point previous. There was something about her that had changed, however, that Gaster couldn't place. Something somewhere had faded. Perhaps she was just aging. "Hello?" she repeated.

Gaster snapped out of his observations. "I heard from Sans that you wanted an interview with someone on my team, to report on the blast cannon?"

She shifted slightly, looking away. "If that could be arranged, yes. If not, I'd understand."

"Well, I'm here right now," said Gaster, with his hands held out in presentation.

"What, do you want an apology?" Verdana snapped. The lights in her eye sockets rolled up and over.

"I meant you could just interview me." He folded his own arms and stared her down. "I can tell you anything you need to know about the cannon, and nothing you don't."

"Oh." Verdana finally turned back and looked him over. "well, I suppose that would work. Right now, you mean?"

"If that's alright."

"Sure, follow me to the recording area," she said, motioning to him as she turned away. "Thanks," she added.

"Thank you for showing interest," he replied. "And by the way, while I don't expect an apology from you, I'd be more than happy to accept one should you have it."

"Ha! In your dreams, chicken wing."

Gaster sighed heavily. "Please don't call me things like that."

* * *

 

Sans had received a text from Alphys shortly after arriving home, inviting him to go dump diving with her that afternoon. He brought his little radio with him, and a flashlight, just in case, and met her there. Together, they set about looking for any device with a working screen.

"It's just so difficult to make them myself," she complained, "too time consuming, not worth it."

"Yeah, sounds like it'd be a pain," Sans agreed, "So we're uh, _screening_ these for water damage, right?" he asked playfully.

"Pffft, yeah. Ooh, the stuff piled on top is probably our best bet, then! C-can you help me get up on this one?"

"Sure." He boosted her up the pile of trash and she pulled him up in turn. It was a balancing act, and they had to be careful not to slip as they climbed.

"So, what have you been u-up to this weekend?" she asked, searching the ground around her with a small light.

"Oh, uh, not much. Learned a new recipe, saw my mom, the usual," he lied, "How about you?"

"Nothing really interesting. I ran into a couple of friends here, yesterday, so I didn't get much looking done. Th-they're- Oh hey, is that Doctor Larkeet?"

"Hey, kids! No running around, I don't want you impaling yourselves on anything!" Dr. Larkeet shouted. A flurry of giggles and the sound of flapping wings echoed after her. "Ruffle, I mean it!"

The two young monsters she was chasing came into view at the base of the trash heap below. "Hey, Larkeet, whatcha doin?" Sans called out to her.

"Sans? is that you? Oh, Alphys too! Hi there!" she called back to them, "I was just- RUFFLE, DON'T TOUCH THAT!- Oh, sorry, it's science fair season. We're looking for project ideas, because the kids just can't think of something safe to make. Pinch, please keep your brother in line."

"Oh, that sounds like fun."

"I'm gonna build a rocketship!" Ruffle, the younger monster, called out, swishing his tail.

"Oh, a rocket's not going to go over well with your teachers," Alphys warned him, "trust me on that one, most explosives don't. Teachers don't notice how much work you put into your project if they spend all their time worrying whether it's going to hurt anyone."

"Really?" he asked, his wings drooping.

"Y-yeah, sorry. Why not look to something safer? You could demonstrate how soundwaves move particles around! You just need a big s-speaker and some sand, I'm sure your mom and sister can help you with the rest."

"There's a speaker over here, Ruffle!" Pinch, the other young monster called out, "Come look!"

"Okay!" He flapped his way over to her.

"Thanks for that, really," Larkeet whispered, shooting them a wink, before following her children down the cavern.

"That's a good project idea," Sans told Alphys, once the others were gone, "safe, but pretty advanced for a middle schooler."

"Thanks," she replied happily, "I used that one my junior year and won first place in a competition. Which was great, but when I went to accept the reward, I knocked it over and spilled sand everywhere..." She sighed. "How about you, got any craaaazy science fair stories?" she asked, waggling her eyebrows at him.

"Aaah, I got one... " he said thinking back a bit, "In elementary school, I got into meteorology for a short time, after watching this one human movie-" his phone buzzed in his pocket, and he pulled it out while continuing his story. "So I really wanted to bring more varied weather to the Underground, and I thought the best way to start would be making a tornado!" Alphys laughed and he checked the message on his phone. "Oh, hey, Gaster's about to be on the radio. Mind if I tune in real quick?"

"Oh! Really? I mean go ahead, but why?"

"Interview, with my mother," he replied, setting the radio down next to him and tuning it to Verdana's station. The news came on and he and Alphys listened while lazily digging through garbage.

                                                                                                __

_"So, listeners! I have one Dr. W.D. Gaster here in the station with me today, to talk about what's been going on at the Royal Science Lab over in Hotland. Doctor, you haven't been on the news much since you started building the Core, why don't you start by telling us a bit about yourself?"_

_"I? I'm not sure what to say,"_ Gaster admitted.

_"Well, for starters, why don't you tell us what that W.D. in your name stands for?"_

He bristled. _"it stands for 'Wonderful Dancer', which I am, of course."_

_"Wh- Okay, that sounds made up, but okay."_

_"You asked."_

_"Well,_ Gaster, _how has your weekend been so far?"_

 _"Uneventful,"_ he said, dryly, _"Yours?"_

_"Not much has happened. One of my sons made some **delicious** clams for dinner. I wish you could have tried them. He works for you, actually. Maybe you can ask him to bring something to work, some time."_

_"Ah, yes Sans, correct? I can see the resemblance."_

  
_"I'll take that as a compliment. Now, would you like to tell our listeners what's been going on at the Core?"_

_"Certainly. We've been busy these last several years maintaining the workings of the core to keep it stable, which is a huge workload. In the last five or six years especially, we've been expanding the reach of the electrical system, so that it spreads out to the entire underground. Or, at least to the more populated areas."_

_"That's really, um... It must be a lot of work, I know the Core is a huge source of employment here."_

_"It is, most of the team I started with when I began the project are now working at the Core full time, and I'm very grateful to them for sticking with it."_

_"You hear that? Let's all give a_ _big 'thanks' to our many friends and family who work on the Core and the Underground Electrical System. Modern life wouldn't be what it is without you guys! Coming up after this commercial break, We'll have Dancer here tell us more about what our scientists have been up to more recently!"_

____

"Is it just me, or do those two seem really tense?" Alphys asked, looking up over her shoulder.

"Yeah," Sans shrugged, "they probably have history or something."

"Y-you don't think it's romantic history, do you?" She brought one claw up to her chin in thought. "I mean Verdana's your mom, right? What if they had a fling or something, way back before you were born? _Ohmygod_ , what if Gaster was like, your dad or something?"

"Alright, I'm gonna stop you right there. First of all, it's not possible. Second of all? I never want to think about that again, like, ever. Ugh." He shivered. The lights had gone out in his eyes, but he did his best to keep his expression playful.

"Yikes. Sorry, Sans."

"Heh, it's cool. No worries." A lot of worries. Sans thanked his lucky stars that it wasn't biologically possible. "Commercial's back over, let's hear what he says about the cannon."

                                                                                      __

_"Alright, and we're back. for those of you just tuning in, we have Dr. Wonderful Dancer, Gaster, here at the station with us, to fill us in on what he and his team have been up to. If what King Dreemurr tells me is true, it's something juicy."_

_"It is! Do you want the long, or short of it?"_

_"Eeerm, I'd really like you to watch your phrasing, is what I'd like,"_ she replied.

 _"Right, well. Sorry."_ He cleared his throat. _"We've been putting together a large blast cannon, powered by the energy of the Core, which we believe will be strong enough to break down the barrier without the use of human souls."_

_"I'm sure we all know by now that our efforts to just... strike the barrier down have been, well, fruitless. How does your idea differ from these past attempts?"_

_"We will use the sound frequency generated by the barrier to weaken it, then overload it with energy, hopefully shattering it. We have made many scientific and magical advancements in the years since our more... crude attempts. And we have the power of the core on our side."_

_"Right, about that," Verdana cut in, "You said this cannon draws in energy from the Core, but how much energy? Can the mechanisms of the core handle that kind of load, and if they can't will the Underground's access to electical power be cut off?"_

____

"Jeez, Mom, asking the real questions." Sans sighed.

"Asgore really should have been the one asking all this before he approved the project," Alphys agreed.

                                                                                        __

 _"Of course, I have taken this all into consideration,"_ Gaster assured her, _"I actually began planning the Cannon way back when I started as lead Royal Scientist, but at the time, local energy systems weren't up to the task of powering something so large and taxing. So the core itself was designed with this project in mind, and it draws in far more energy than we typically use, storing some in reserve in case something interrupts the main electric line. We actually have the ability to double the reserve as well as increase general intake. Firing the cannon at full force will definitely drain reserves, but shouldn't cause more than minor interruptions."_

_"Wow, well, it's good to hear you planned something out. When will you be firing the cannon, by the way?"_

_"As of yet, we don't have a deadline for its completion, but rest assured that we are all working diligently toward its completion. Your son, included. We should have it ready within a month or two, and we will notify the public before we fire, so they are aware of any possible interruptions to their electric service."_

_"Good, I'm glad you've thought all this through. Honestly, Asgore was pretty excited to tell me about this project, but he didn't have many details. Oh!, it looks like we're out of time for this segement. Dr. Gaster, thank you so much for your time."_

_"Thank you for yours."_

_"Alright, listeners, stay tuned for our segment on diagnosing and dealing with depre-"_

____

Sans clicked off the radio as his phone went off in his pocket. He pulled it out to find another message from Gaster.

' _I think that went well. She didn't apologize, and neither did I, but she didn't flay me, and I think that counts for something.'_

 _'You did pretty well,and you sounded great. Good job, Doc,'_ he replied. He turned the screen off and was shoving the phone back in his pocket when it buzzed again. This time, was a message from his mother.

_'ALL RIGHT, SO IF YOU MISSED MY INTERVIEW WITH YOUR... BOSSFRIEND, IT'LL AIR AGAIN ON WEDNESDAY EVENING. I JUST WANT YOU TO KNOW THAT I HANDLED THE WHOLE THING VERY PROFESSIONALLY.'_

Sans laughed so hard he nearly dropped his phone into the garbage.

**Notes for the Chapter:**

> Radio, what's new?  
> RADIO? SOOOMEOOOONE STILL LOOOVES YOOOOUUUUU!
> 
> Sorry for taking so long on this one. it got a bit longer than I was expecting.


	34. No shortcuts

"Hey, Doc, are you here?" Sans called out, as he teleported into the cannon room early Monday morning. The question had hardly left his mouth when he noticed Gaster standing across the room from him, with one hand in the dark of the storage closet.

"Hm?" Gaster jerked his head toward Sans, and slowly pulled his hand from the void.

Sans flashed him a smile. "I was wondering why I couldn't get in that way. Having fun?"

"Studying," Gaster corrected him, "not just jumping in and skipping about in there, alone." He gave Sans a pointed look. "I'm exploring slowly and safely."

"Okay, yeah," Sans said, shrugging as he strolled over to where Gaster stood, "but in the time I've spent in there, skipping about willy-nilly, I've actually figured out a lot about how it works."

" _A lot_ ," Gaster repeated, "but you could have gotten _stuck_ in there, or _hurt_. That little beast is still loose and has untold access to this space, if you've forgotten."

"I haven't forgotten." Sans reached up and stroked the frame of the door. "I mean, maybe it's not the safest place to be alone, but I've been alright. I'm safe."

Gaster huffed a little at that and dissolved his enchantment on the door. Sans rolled his eyes as the doctor turned away. Hadn't Gaster been the one to try and stick his hand in before they even knew the void was a habitable space? And now he was giving Sans shit about not being safe. Sans was safe. Sans was never in there longer than he had to be.

"Okay, but anyways, before anyone else shows up down here, I have an idea on how we can put this whole thing to use here at work, and I think you're gonna like it."

* * *

  
Gaster wasn't terribly fond of Sans's idea. "I'm not terribly fond of the idea," he said plainly.

"Okay." Sans slumped against the wall behind him. "Why not?"

"Why n- This cannon," the doctor reached over and patted the shell of the cannon for emphasis, "this delicate and powerful machine? It may only seem like a few weeks' worth of work to you and anyone else who's new here, but it represents years of work for me. Forgive me if I'm not agreeable to dragging any part of it through unknown space just to save _a few days'_ worth of work transporting it out. You could lose it, or worse, it could get damaged. You admitted yourself that the void space interfered with your cellphone's functionality, yes? What would all that pressure in there do to the firing mechanism? How would we get it to work again if it quit on us?"

Sans sighed. "So, we could transport all the electric and mechanical pieces on foot, then. The shell's most of the bulk, anyways. And if we go by Juneborg's disassembly plan, we're cutting it into eighteen pieces. It's almost an hour's walk to the castle from here, so that's up to thirty-six hours for the shell alone. Not to mention the time spent taking it apart and putting it back together. It could take me until the end of next week if I don't stay late. I will stay late, by the way. But it could be the end of _this_ week, if you let me transport them through the void." He shoved his hands into his coat pockets and sighed. "By the way, my cellphone works just fine once I'm outside of there. Your hearing aides, too. You should know that."

"My. My hearing aides?"

"Yeah. Probably why you couldn't hear much of anything while you were in there."

"That... makes sense, I suppose." And Gaster kind of hated to admit that. Sans had chided him for merely attempting to put his _hand_ in, had he not? And now he was jumping about, willy-nilly, exlporing at a much faster pace than Gaster would have deemed safe. But he was making discoveries. "Any other **neat tips** you've figured out, while you were in there?"

"The enchantment doesn't work on thin air, and the void doesn't open up everywhere. Just doorways, I think. Windows, maybe. The uh, spaces that connect one place to another."

"Hold on, I'm going to write this down," said Gaster, moving over to the open file he had begun keeping on the void. "Anything else?" he asked, grabbing a pen.

"Nah, that's most of what I got. I could still be proven wrong, but so far, I haven't come out any place that isn't a doorway."

"Hmm." Gaster tapped the pen against the paper as he finished writing, and began thinking. "Sans?"

"Yeah?"

"Your ideas haven't failed me yet, did you know that?"

Sans's face flushed. "No, I didn't."

_How cute._ "I trust you, and you make a fair argument for your plan, but you're not infallible. Get to work on disassembling the cannon, while I think this idea over. By the time you've got the whole thing taken apart, I'll have made up my mind on the matter. Does that sound fair?"

Sans nodded. "It sounds fair, yeah. Thank you, for thinking about it."

"Hm. If you run into any problems, let me know. Also, until you're finished, stay _out_ of the void space, unless I'm there with you, is that clear?"

"Wait, you mean completely, or-"

"Completely, yes. if you're causing any interference by going through all the time, we may not be able to study it properly."

"That sounds like a made up reason."

"How about 'I want you to be safe', then?" He asked, giving Sans a more pleading look.

"Okay, that's... that's reasonable."

Gaster wondered if he'd ever tire of seeing that blush spread out across Sans's face.

* * *

 

Lucky for Sans, disassembling the cannon was easy, especially when Juneborg had made an annotated copy of the plans for him. He stayed in the cannon room for most of the day, taking pieces of the shell off and labeling them with chalk for future reference. While he worked, Gaster bustled about all across the lab, getting things in order, and conversing with the other scientists as they showed up.

Dr. Larkeet and Juneborg appeared to give a brief progress report on Project Disco, before heading out again. Things were going well, even though the workers at the core were a bit disorganized, and some electric lines had gotten switched around when they wired the place up. Nothing a little re-routing couldn't fix, Juneborg had assured them.

Wickett showed up a little bit later, to bring in the human-soul-data that had been gathered over the weekend. He decided it was necessary to lead Gaster out of the room for that, speaking in hushed tones, but Sans couldn't really complain with a screwdriver in his mouth and wires in his hands.

Gaster wouldn't explain why they had gone off, when he returned, but he also didn't seem bothered about anything. He assured Sans that Wickett's behavior was fairly typical. "He's always like that when he's sure he's onto something. But it's not that important to what we're doing. By the way, what would you like for lunch? My treat."

Sans's appetite was lacking as he looked down to the large glass eyeball sitting between his hands, but he figured a light lunch wouldn't hurt. His break went by far too quickly, after Gaster had come back with food, and he got back to work immediately.

Two hours after their day had ended, and Gaster told him it was time to go home. Sans sighed contentedly as he looked over the dent he had made in the cannon's disassembly. The upper jaw had been unhinged, and now half of it was gone, stacked neatly in the corner of the room. Not bad for one day's work.

He wished Gaster goodnight, and headed up to the office to file his report on his scope's data for the day, because Gaster insisted it keep running until they were ready to fire the cannon for real. Wickett was still around the office area, seated at his computer with a hefty stack of papers on his desk. It looked to Sans like he was transcribing all the data they had gathered on the human souls so far. He didn't look up or speak when Sans arrived, or when he left for the day.

Sans shrugged it off and headed home on foot, no shortcuts.

Tuesday was mostly the same as Monday had been. Mostly. Sans had found a ball of dog hair in among his toolkit upon arrival, and another wrench was missing. But he checked the pieces of the cannon for signs of damage, and there was nothing. He thanked his lucky stars, disposed of the fur, and decided not to tell Gaster about this particular intrusion. The doctor already seemed troubled by something that morning.

At lunch, he found out what had been troubling Gaster, when the doctor pulled Sans into his office and sat him down.

"So, I decided to check through the weekend's security footage last night, around the time you left." He drummed his fingertips against his desk.

"Yeah?"

"Yes. Including the footage from Friday. Friday evening, in the lobby of the lab. That bit was interesting." He cleared his throat.

It took Sans a moment. So much had happened that weekend, but when he finally caught on, he laughed out loud. "No way. You were recording that?"

"Well," said Gaster, a bit defensively, "I'm always recording in certain areas of the lab. But I want to know what you think I should do with the footage." He looked uncomfortable, and Sans fought back a second wave of laughter.

"Heh. You're gonna delete it, right? What else is there to do?"   
  
Gaster didn't answer.

"I mean, I'm sure we were breaking some rules there. Isn't there a rule about canoodling in the laboratory?"

"Nothing specific," Gaster mumbled, blushing.

Sans laughed again.

"Would you like me to delete the footage, then?"

"Well, let me see it, first."

After he had made his decision, (and gotten a few laughs out of the situation,) he set back to work. He needed to find a replacement wrench for the one the dog had stolen, (That thing had a real taste for metric wrenches), he fell into an easy rhythm, mirroring his work from the day before, and pulling ahead to finish the other half of the upper jaw by the end of the day, despite earlier setbacks. Just as he was packing up the pair of unnerving glass eyes, Wickett strolled into the room to knock on Gaster's office door. This time, he spoke loudly enough for Sans to hear him as Gaster cracked the door open.

"Just wanted you to know I'm not staying late tonight," Wickett said. "Doctor's appointment," he added, gruffly. Gaster waved him away and bid him good night, before turning his attention to Sans.

"Are you staying late?" he asked, looking over what Sans had accomplished so far.

"If you need me," Sans replied.

Gaster nodded, "I'd appreciate your help with something, if that's alright."

"Yeah, I'll stay. Have a good night, Wickett. See you tomorrow."

Wickett waved silently back as he turned to leave.

"Okay," said Sans, once he was gone, "what do you need?"

"I need you to accompany me into the void space, I'd like to test something."

**Notes for the Chapter:**

> Sorry for my tardiness.
> 
> Next chapter's gonna be something a little different from the norm. :-3


	35. It happened on a Tuesday (it's always a Tuesday)

**Notes for the Chapter:**

> This chapter is in a slightly different format from chapters previous. To keep this as simple as possible, it goes:
> 
> Past, present, past, present, past, present, past, present, past, present, ???
> 
> Each takes place on a Tuesday.
> 
> WARNINGS FOR THIS CHAPTER SPECIFICALLY: There will be mentions of Body-modding (not sure if that reaches body-horror levels for anyone, June's a cyborg), grieving/mourning, King-Dings, Dog bites, Wickett's organs (not gore!), and FINALS.
> 
> I'll update the work's tags before I post the next chapter, please keep an eye out for that when you go to read it.

Gaster found out quickly that the most uncomfortable thing to sit on was vital, life-changing information. He fidgeted and kicked up snow while the woman, his friend on the other side of the door, spoke about recent happenings in the ruins. It didn't take her long to catch him up on the goings-on of a place known for being small, empty, and quiet, but she rambled on happily, oblivious to all the things he knew about her now that he had figured out her name.

Had he known it would turn out this way, all those years ago when Dr. Marlick sent him on that fool's errand to try and find a way into the ruins, he might have done some things differently. Been kinder at first to the woman whose magic was keeping him out, perhaps. 

"... But of course, by the time I finish raking them all up, there are more growing that are just about to fall. I've decided to leave them, it's not like they're doing any harm," she concluded. Her story, as usual, had gone nowhere, but Gaster didn't mind. She was sweet and he liked listening to her talk. "But enough about that! Tell me, friend, how are things going with you and your beau?"

He grimaced and clenched his teeth, though she couldn't see it. "Things are going well," he mumbled, "I think I'm going to break up with him, though." He really didn't want to talk about this, but perhaps it was necessary.

"I'm sorry, I don't think I quite caught that, what did you say?"

"I said I'm leaving him!" he shouted to the door.

She gasped. "What?! Why? Last time we spoke, things were going so well, were they not? I thought you were going to tell him you lo-"

"Your majesty, I regret to inform you that I have, in fact, been sneaking around with your _husband_ these last eleven months!"

There was silence on the other end of the door. Had she walked away? Half a minute passed before she spoke, quietly and carefully measured. "I think you have the wrong person, friend. I do not have a husband."

"Toriel, I know it's you. I've known for a few weeks now. I've had my guesses for far longer, mind, but you sealed it when you spoke to me about your late son's birthday, last month. Asgore had mentioned it as well."

He could hear her shuffling about. "Asgore, King Dreemurr, is the mysterious sweetheart you've been telling me about all this time?"

"Yes."

"You made him sound so _nice_ , when you talked about him."

Gaster laughed, dry and humorless. Asgore had painted a lovely image of her to Gaster, as well. Always with a sad, longing look in his eyes. But none of the details were wrong. Toriel was as sweet and fierce in person as the king had described. "Surely he wasn't all bad when you knew him?"

"But you know why I left?"

"I'm aware, yes."

"... is that why you...?"

"Unfortunately, I have a long list of reasons why it has to end. I've been thinking about all this for quite a while now. But among them is the discovery that he's married. To one of my own friends, no less. I can't in good conscience continue to call myself your friend while in bed with the man you married."

"No, you do not have to worry about... about my return, I am not coming back. If you two are happy together, you have my blessing."

If only it were that simple. "He's not happy, I don't think. He's not lonely, I make sure of that, but there isn't much I can do to alleviate his sadness, his depression. It runs too deep."

"Oh, _Well!_ I am just to sorry to hear that _he's_ depressed!" she hissed, "I wonder, though, what he _thought_ would happen, when he started all of this."

Gaster flinched. She had a point, after all. "I'm sure he regrets some of the more hasty decisions he's made over the years."

"Yet he keeps making them."

He groaned internally, unable to disagree with her.

"My apologies. I hope you truly have thought through your decision, though."

"I have. I am not entirely happy with my decision, but I have thought about it thoroughly."

"What are you going to tell him?"

"A half-truth. I am actually concerned for my own future. If it gets out that I've been involved with the one responsible for choosing the next Royal Scientist, after my superior leaves, my career would be over before it began. Best to play it safe, for now, cut my ties to him, even if it hurts my chances of advancing. I won't tell him about you."

"Thank you, dear. I appreciate that very much."

* * *

 

Juneborg had a screw loose. A big one, apparently. She tapped it nervously against the surface of the desk as she tried to trace where it could have fallen from. Not her new installation, surely. She pressed her other hand into her wrist, feeling the surface of her new voltmeter, securely in place, right under the laser.

This thing was too long to have fallen out of there, anyways. She scooted her chair back and checked both of her knee plates, under her arms, the back of her neck, everywhere she could think of. The radio under her right antenna buzzed static, always unable to pick up a good signal from her room. She reached up tentatively for the volume knob, to turn it down. The knob was still there.

She sighed, clicking her mandibles angrily. it had to have come from somewhere. She didn't want to figure out where by losing a piece of herself later on. Looking back down at the screw, she couldn't help but wonder why it didn't even look _familiar._ It was a darker metal than the ones she currently used, and the tip was sharply pointed.

Had she ever used pointed screws on herself, in any of her modifications?! _No, because that would hurt like hell if it breached her exoskeleton!_

There was a knock at her bedroom door. Her roommate called out, without waiting for a response. "Hey, I was putting together some furniture this morning, and I think I messed up somewhere. I'm missing a few pieces, so if you see any nails or screws lying around, let me know, okay? And don't set anything on the new bookshelf yet!"

Juneborg sighed in relief and fell backwards onto her bed, laughing as her roommate walked away. She clenched her fingers around the screw and-

"Wait, where'd it go?" she asked herself, groping the covers, "Nooo! I just had it!"

* * *

 

Sans was on his way home from school when the dog approached him. His mother had warned him once to be wary of larger dogs, him being made of bones and all. But this one wasn't a very large dog at all, maybe half his size. "Hey there!" he called to it as it filed in next to him. Its tiny paws pattered on the cobblestone as it kept pace with him. He slowed down a step or two, and held his right hand out to it, his left clutched firmly on his backpack. "My name's Sans, what's yours?" The critter cocked its head to the side, and Sans chuckled. Maybe it couldn't speak, not all monsters could. They stopped walking and he pushed his right hand out further toward the dog, hoping maybe it at least knew how to shake. "What's the matter? Don't you know how to greet a new pal?" he asked, playfully.

The dog yipped happily, and immediately chomped down on the hand that had been offered. A scream of pain rose to Sans's mouth, but by the time it came out, he was being pulled off in another direction, toward an alleyway. Sans winced and gritted his teeth as he was dragged over the bumpy surface of the cobblestone road. A particularly large stone scraped against the side of his ribcage, and he cried out sharply when suddenly, there was nothing below him.

At least, it didn't feel like anything he was familiar with. There was a sudden pressure around him on all sides, and he opened his eyes to find...

**Nothing.**

The dog had vanished, the street he was walking along had vanished, and all around him lay a vast, heavy nothingness. He called out for help, but his voice fell short, like a candle trying to cut through fog. His right hand hurt, he was sure there was a chip in his ribs somewhere, and he had no idea where he was. Was this karmic punishment for that one time he wished he didn't exist? Tears welled up in his eye sockets, and he brought his hands up to wipe them away, and it must have been because his eyes were closed, that he didn't see the dog return. But he looked up to find it sitting there, wagging its tail and panting.

He had no time to react before it leapt forward, snatching his hand into its jaws again. Its teeth grazed his face, nearly latching onto the edge of his eye socket before he was once again pulled sharply forward, downward this time. He felt curtains brushing past him, and then suddenly there was light around him, much too bright for his eyes to adjust immediately.

The dog relinquished its grip on San's hand, and he immediately scooted himself backwards, frantically trying to put as much space between him and the beast as possible. His back met some sort of wall, and he sobbed as tears rolled down his cheekbones.

"St--stay away from me," he mumbled, unable to find his voice. The dog cocked its head to the side, then leapt forward again, to lick Sans right in the eye. He screamed and flailed his legs, balling his hands up into fists, he tried to push the dog away, but it was already gone.

Above him, something opened, and he looked up to find his mother, Mollig, staring down at him.

"Sans, is that you? What's going on, Sweetie? Why are you home from school early?"

"Early?" he repeated, quietly.

In the distance, he could hear the school bell ring.

* * *

"So, how are you feeling?" asked Wickett's practitioner, Dr. Foot.

"Not too great," whispered Wickett, "Kinda hurts to talk."

"But whispering helps?" her voice dropped in volume to match his, probably subconciously.

He chuckled, then winced. "Little bit," he replied.

"Hmm, well, our tests showed that you do have some hardened wax in your esophagus, and also your stomach. We also found water in your system."

"Shit."

"Now, I'm not going to ask how it got there, because that's none of my business, but if you know, I'd recommend avoiding whatever it was, in the future."

Wickett sighed, angrily. "Steam, probably, there are a few vents around the area." It was a damn snow cone, is what it was. Not even a good one, he had no idea why people decided flavoring snow was a good idea but hell if he hadn't been dying to try it.

"Now, as for the damage..."

"There any way I can fix it with magic?"

"You mean your fire magic? _No_ , goodness no. You might melt the wax, but there's still water in your system, and it can continue to damage you as long as it's there."

He scowled. "So then, what do you recommend?"

She looked up and toyed with the stethoscope around her neck, humming in thought. "Magma, perhaps," she finally replied, "Or lava, I always forget what the difference is."

"Oh! Magma! That's great!" Wickett's voice was scratchy, and he winced even as he continued to shout, "Why don't I just reach down in there and scoop out a big old jug full? In fact, while I"m out there, I could just go swimmin' in it! Rejuvinate myself from head to toe!"

"Calm down, there's no need to shout," she said, folding her arms, "I wasn't thinking of the magma in Hotland, I'm talking maybe the magical kind. I've got another patient who's literally overflowing with the stuff. I'm sure she'd be happy to donate some, and it'd be enough to melt your insides back to the correct temperature, as well as maybe evaporate that pesky water that's still hanging around."

"So that's your plan, for me to drink some mysterious lady's **body lava**."

"Well, unless you want to start eating towels? We could do that, it wouldn't be the first time I've prescribed towels to someone."

"Call her up then, lemme know what she says."

"Excellent! I'll get back to you as soon as I have an answer from her. In the meantime, I'm going to need you to stay away from any cold foods, and maybe also don't drink any oil until we've gotten this taken care of."

"Wh- No oil?!" How was he going to make it through the week if he couldn't have any oil?

"Doesn't mix well with water."

" _Fantastic_. Anything else?"

"I've got some pain-relieving lollipops I can send you home with."

* * *

 

Asgore was always warm. Monsters with fire-affinities almost always radiated heat, so it wasn't unexpected. But the _way_ he was warm, it was soft and comforting, like a freshly-dried towel, or an electric blanket. Gaster hadn't realized how much he missed it.

The king shifted in his sleep, and Gaster's gaze drifted slowly up from the arm of the plush chair they were sharing, to look him in the face. He looked so exhausted, even while resting. Gaster sighed, resigned, and scooted in a little bit closer, under one of Asgore's arms. He scowled at himself for enjoying such contact. What would his friend Toriel think, if she knew how weak he was? It had been two years since his relationship with Asgore ended, officially. A year and a half since he had been appointed Royal Scientist, officially.

Twice now he had found himself back in Asgore's arms, off the record. It didn't mean they were back together, no. They were still just two lonely aquaintances. Too lonely.

Reluctantly, Gaster forced himself up slowly from his comfortable position at Asgore's side. The other monster sighed, but did not stir. Gaster knew this wasn't going to work, that both of them were only going to hurt more if they kept relapsing like this. He was going to have to stay busy, stay unreachable, if his own willpower wasn't enough to hold him away. Lucky for him, now that construction had begun on the Core, he was probably going to be tied up with that until it was completed. He hoped so, at least.

He leaned forward carefully, bracing himself on the arms of the chair, and gave Asgore a gentle kiss on the cheek. His pulse raced as Asgore shifted, then settled back into stillness. Gaster sighed with relief and slipped silently from the room, afraid to look back.

His heart hurt, but this was for the best.

* * *

 

"Aright, Ruffle, the plate is securely attached. Go ahead and pour on the sand. Not all of it! There, that's good." Larkeet watched carefully as her son poured sand over the metal plate she had connected to a large, homemade speaker. He spread it out evenly, and she put a wing on his shoulder. "Now, this is a pretty powerful speaker," she informed him, "what do you think is going to happen to the sand when we turn it on?"

"Ummmm..." He fidgeted with his plumage as he thought. "The sound's gonna be really loud, and the sand is gonna just, fly right off of there!" He splayed his wing feathers to emphasize his point.

She giggled. "Alright, that's a pretty good hypothesis, go ahead and write that down in your logs." Once he was finished, she turned to her daughter, Pinch, who had volunteered to operate the speaker controls for them. "Alright, Pinch, set that baby to 400 hertz, to start with, and turn the volume up slowly."

Pinch nodded eagerly, and fiddled with the controls until they were where she needed them. Then, all three of them watched as the sand came to life, particles dancing across the speaker to form a geometric pattern.

Ruffle's feathers puffed out, and he gasped excitedly. Larkeet handed him her camera, and he took three different pictures of the pattern.

"Woah there, son! Save some film for what's coming up. Pinch, 600 Hz, please?"

The pitch increased, and the pattern changed. Ruffle quickly snapped another picture, and Larkeet made note of the frequency on another sheet of paper. They increased the pitch a few more times, in intervals of 200 Hz just to keep things simple, until Larkeet called it quits.

"Okay, after seeing the results of your experiment, how does your hypothesis hold up?"

"It doesn't. I didn't think that would happen at all!" he exclaimed.

"Well, write that down then!" She watched him scribble away on his experiment log. "Any idea what we could have done differently?"

He looked down at the speaker for a solid minute, thinking. "If we got the speaker going loud enough, maybe it would have blasted the sand off," he said, finally. "But what I wanna know is, why did we use sand? What would have happened if we used water, or rocks? Does it still happen the same way, with the patterns and stuff?"

Larkeet's chest swelled to bursting with parental pride. She could feel some of it leaking out of her eyes as she beamed down at her son. "Those are all excellent scientific questions, my boy! Why don't we find out?"

* * *

 

The funeral had passed without incident, friends and family had all come by to say their goodbyes and reminisce. But at the end of the day, with all the ceremony over, and visitors gone, Verdana still clutched her wife's urn tightly to her chest.

Sans sat at her feet, looking up at her hollow, tear-stained sockets that did not look back at him. "Are you going to be okay, Mom?" He asked with a sniffle.

She sank further into the couch, squeezed the urn closer to her chest. "I'll live," She said, quietly. Her voice was raspy and faint from spending the last two days crying. "It'll be hard, but I'll live."

He nodded solemnly, looking away. "Where are you going to spread her dust?" he asked, cautiously. It couldn't stay in the urn forever, that's not how things worked.

"I was thinking her brush, the soft one... or her oven mitts, maybe. I don't know, we never talked about this." She sobbed, but no more tears left her eyes. "I never wanted to talk about it."

Sans heard stirring from his and Papyrus's bedroom. "Mommy?" Papyrus called out, groggily.

Verdana cringed, he wasn't calling for her. She was always 'Mama', never 'Mommy' Sans stared down at the urn, with painted letters that spelled out the name Molligander Thegret-Calibri. He kept staring until Verdana spoke, startling him.

"Go take care of him, please? I can't I just-"

"I'll read him a story," Sans offered, "that'll put him right back to sleep."

"Thank you. I'm sorry, it just, hurts to move right now. I don't want to get up. Losing someone is hard, it's hard, Sans."

"It's alright, Mom," Sans assured her, making his way to the bedroom. They all hurt, but he figured Verdana hurt more, having known her and loved her for much longer than he or his brother. He slipped into his bedroom, and sat down on the bed next to his brother. "Mom's tired," he explained, "so I'm gonna read you a story, that okay?"

* * *

 

"Finalllllllls," Alphys groaned, rolling over on her bed, "Oh. My. God. Finals."

She stared blankly up at the ceiling, weighing her options. So many options. She could study for her upcoming finals, the most important tests she would ever take in her life. That was something she could do. But! She could also do any number of things that weren't that, like watching anime! Or going to the library and checking out every book they have about embroidery! She had no previous interest in needlepoint, so learning everything there was to know on the subject all in one week would be extra-impressive.

Not to her teachers, of course, but to the other hobos she was inevitably going to spend her life with, because she was definitely going to FAIL her finals.

She growled and reached for her remote. pointing it behind her head, she turned on the TV. Maybe some cataclysmic event would force the university to cancel finals, and they'd feel so bad about it that they'd give her a degree, anyway. Sure, that could happen.

* * *

 

"Hey, Sans. How would you feel about a 'study session' at my place, this evening?"

"Ha ha, it's funny, because I'm actually studying, for once," Sans said dryly. He kept reading, turning the page in his textbook without looking up, "talk to me when finals are over."

"Like, finals finals? I thought you still had another semester to go."

"It's pretty much all electives. I'm gonna try to test out of the one class I actually need." He turned to his notebook, wrote something down, and resumed his place in the textbook.

"They're really gonna let you do that?"

"Yeah, pretty cool, huh? Heard through the grapevine that Dr. Gaster's gonna be hiring a bunch of people this spring. I gotta at least have my bachelor's degree by then." He took a deep breath. "If I don't get hired, I'll probably come back to school in the fall and shoot for my doctorate. But I'm aiming to get hired, so... talk to me after finals."

"Man, that's too bad," they said dramatically, sitting themselves on the one clear space on his desk, "this offer's only good for tonight. Looks like you picked the worst possible day to start studying."

Sans watched as they stretched their legs out, then tucked them under the desk, crossing them at the ankles. "My loss, I guess," he said, grinning up at them.

"Damn straight," they replied, sliding off the table and striding away. "I'll get back to you after finals, though. Help you celebrate or something."

* * *

 

Gaster wanted to keep their time down to an hour, they ended up running a little over that.

The experiment started out simple, bringing expendible electronic devices into the void with them, seeing if they worked. Of the twelve devices they brought with them, three remained functional: A wind-up toy, a calculator powered by magic instead of electricity, and a lamp that was plugged in to the wall outside. The bulb had flickered and dimmed when they brought it in, but it continued to work, which was a good sign. Gaster didn't appreciate the effect the light had on the void around it though, causing it to shimmer and shift in a way that made him queasy.

Finally, he deemed it safe to bring in one of the prototype blasters, the smallest one. It wouldn't fire inside the void, which was probably for the best, but it worked just fine once they got out. Gaster made note of this, casting a sidelong glance at Sans's wide grin.

After all was said and done, he sat down, looking over his notes. "It looks promising, your idea," he told Sans, "but I still need to think it over. In the meantime, continue to keep out of the void space, alright? I still don't want anything happening to you."

"Yeah okay," Sans replied shrugging, "I'll listen to you... if you give me a smooch."

Gaster raised a brow at him. _You'll listen to me because I'm giving you an order_ , he thought, but he leaned in nonetheless, until his face was inches away from Sans's. "Go home, Sans," he whispered, smiling, "get some rest."

"You too," Sans whispered back, bridging the distance for a quick peck.

Gaster diminished the enchantment on the storage closet, then waited until he was sure Sans was in the elevator, before getting back to work. In ten minute's time, he had modified a small recording device to run on outlet power, like the lamp. He cast his enchantment again, and stepped back inside the void, letting the cool, dark pressure wash over him. It helped to sooth what little nervousness he was experiencing about stepping in alone.

Now that he was expecting it, he could tell exactly when his hearing aides cut out. He flicked the switch on the recording device, as the sound of rushing particles flooded his senses. He checked to make sure the divice stayed on, but wasn't entirely sure it would pick up on the noise he was hearing, let alone how it was beginning to change.

* * *

 

The cold air was doing nothing for their joints, or their breathing. They waited until the door closed behind them before falling into another coughing fit. The harsh, wet sound echoed in the dry air around them, and every inward breath was agony. Eight hours, they could do this. No slips, no falls, no dangerous encounters. They would make it to the castle, and then they would leave and get to a hospital. It was their only chance of surviving.

"Third time's the charm," they told themself.

**Notes for the Chapter:**

> I couldn't decide when planning this chapter, whether it should be slice-of-life, or flashback city. It ended up being both.
> 
> [If you wanna see the experiment Larkeet and her kids were doing, here's an example.](https://www.youtube.com/watch?v=wvJAgrUBF4w)
> 
> The person flirting with Sans is probably the same one who shared their family recipe for steamed clams, who knows? (it's honestly not important)


	36. Wednesday

**Notes for the Chapter:**

> Sorry for my tardiness! I hope the slightly-longer-than-usual chapter makes up for it.  
> Also it's been a strangely busy week.

Gaster woke early Wednesday morning in his office, to the sound of the lab's phone line ringing. Half asleep, he pried himself from his cot and shambled over to pick it up only to drop the receiver immediately back into place, ending the call before he could answer it.

"Whoops," he mumbled, "I didn't mean to drop you, please call back." After a minute or so of silence and fighting to keep his eyes open, he gave up on waiting for another call.

It was nearly time to get ready for work, anyways. For some reason his cellphone alarm hadn't gone off to wake him sooner. Picking it up from its spot by his pillow, he realized that the battery must have died at some point during the night. No matter, he was awake now, and had plenty of time to charge it. After plugging it in, he donned some spare clothes kept under his cot and headed to the upper floor to begin his day. Sans and the scent of strong coffee greeted him in the lobby.

"G'morning, Doc," said Sans, groggily.

"Morning," Gaster replied. He checked to make sure no one else was in the lobby, then moved behind Sans to rub his neck and shoulders. "I really do hope you'll let me have some of that, it smells wonderful."

"Heh, you look like you need it." The skeleton sighed contentedly and rolled his head back into Gaster's touch. "Did ya sleep okay?"

"I was up for a while, tinkering with something. You?"

"Reading through those books you lent me." The coffee having finished brewing, he reached up and switched the machine off. "Cream and sugar?"

"Both, _please_." Gaster leaned down to plant a kiss on the back of Sans's skull just as the the door to the lab opened behind him. He whirled around quickly to Greet Juneborg as she stepped in, and prayed the heat on his cheeks didn't show. "Good morning, miss Borg!" he said, just a little too cheerfully, "How is Project Disco coming along?"

"Just groovy, doctor!" she chirped back in an equally cheery tone. "Dr, Larkeet told me to say that," she then admitted, "I've come to give you a progress report."

Sans stepped up beside Gaster to hand him his cup of coffee. "I'll be upstairs, gotta check on the scope."

Gaster nodded and took a big swig from the mug of coffee as Sans walked away. Turning back to Juneborg, he could finally feel the last of his drowsiness subsiding.

"Alright, lay it on me," he said excitedly, "I want the details, how are things?"

"We're almost finished, actually! Larkeet thinks we might be done at the end of this week, or early next week. At least we will be, if there aren't any more delays..."

"Mhm." Gaster nodded, taking another sip of his coffee.

"I mean, everything on the Core's end is ready, all we have left is to get things set up at the palace. But things are a little hectic there right now, everyone's on guard, and it's hard to work around all of them. So um, I guess we'll see?"

That didn't sit right. He pulled the cup away from his face to speak properly. "What do you mean things are hectic? Did something happen?"

"Do you not listen to the news?" June asked, hunching in on herself. "I mean, it happened super early this morning, but everyone's been talking about it."

"I was here all night, I haven't had the chance-"

"Gaster? Dr. Gaster, I mean, fuck," Sans cut in from the top of the stairs, "Sorry to interrupt, but I think something's wrong with the scope. Like, really wrong."

"I'll be right up," the doctor called back to him. Turning back to Juneborg, something in his gut twisted. "What happened?" he asked again.

"A human came through the Underground Last night," she said, quietly, "King Dreemurr took care of it already, but everyone's a little jumpy right now, and the guard's a mess. I'm sorry, I thought you knew."

* * *

 

In the weeks Sans had been using the oscilloscope to monitor the barrier, the resonance frequency had shown little to no variance, aside from the day he and Wickett had tested the effects of blue magic. Any other interference, any change from the norm, should have been immediately noticeable, if only because the frequency never really shifted otherwise.

In one night, the scope had shown more activity, more change than Sans had seen in well over three weeks. His first thought was obviously that something was wrong with the scope itself. The barrier didn't just _behave_ that way. Gaster came up the stairs shortly after to see what the matter was, with Juneborg in tow. Once June explained what had happened the previous night, things started to make a little more sense.

"Look," she said, pointing to the spot on the graph where the frequency began to return to normal, "this is right around the time the human was slain, and there haven't been any shifts in the data since, right? That must have been what was interfering with the barrier's frequency."

Sans turned to Gaster, who wore a pensive expression. "Doc, what do you think?"

"Hm?" Gaster responded, jolting. "No, that makes sense, the scope's probably fine. You can go check on it if you need to, but..."

"But there's a lot going on at the castle right now," Juneborg continued for him, "Dr. Larkeet and I were having a hard time getting around everyone to work."

 _Well, I could probably just pop in there if Gaster would let me,_ thought Sans.

"I'm taking the rest of the day off," Gaster suddenly announced, turning away, "If anyone needs me I should be down at the palace. I need to talk with Asgore about what happened. Sans?"

Sans straighened his back in his chair. "Yes?"

"I've made my decision, we'll go through with your plan to move the cannon. It's probably the only way you'll be able to get to the barrier now, anyway. I want that cannon functioning again and ready to fire as soon as possible. If that means working over the weekend, we'll work the weekend. Juneborg?"

"Yes, Dr. Gaster?"

"Please call Dr. Larkeet, and see what she wants you to do. Let her know we need Project Disco completed as soon as possible, delays be damned."

"Alright," she responded, her antennae twitching, "If you're going down to the palace, do you want me to wait for you?"

"No, that's fine, I'll go on my own. I have something to take care of first, anyway. If either of you see Wickett, tell him I need one of those smaller scopes hooked up to monitor the new soul, if he can get into the mausoleum. We'll see if it's any different from the others. It shouldn't be, but I'd like to make sure. After that, he can help Sans reassemble the cannon. Is that all clear?"

"Yes sir," Sans and June replied simultaneously.

"Good, I'll see you all tomorrow, then," and with that, Gaster turned away and fled quickly down the stairs.

Sans closed out the program and turned off his computer. "Well," he mumbled, "the week just got busier for us, didn't it? What is that now, six human souls the king has?"

"Yeah," Juneborg replied, "I can't believe we're so close already. I hope this works, though. I heard on the news, this human didn't really do any damage, but others that've come through? It hasn't been so peaceful."

"Really?"

"Mhm. My great uncle was killed by a human that fell down here, a long time ago. I guess it was just a kid, but it took him down like he was nothing."

"And we want to badly to get to the surface, where there are more of them?" Sans chuckled dryly.

"I mean, I guess it's better than being stuck down here." She whispered, twiddling her fingers, "Anyways, I should get going, I guess we're all under a stricter schedule now."

"Yeah, I'll probably see you out there. Be safe okay?"

"I should be telling you that. Are you really moving that whole cannon by yourself?"

Sans shrugged. "I can handle it, I've got my ways."

"Okay, sure, be mysterious about it. I don't care." She returned his shrug and made to walk away, but stopped after two steps and turned back around. "Actually, while I've got you alone, I wanted to ask you something," she said in a low tone.

"What's up?" he asked, cautiously, turning in his chair to face her directly.

"Was Dr. Gaster trying to like, put the moves on you earlier, or something?"

Sans froze in his chair, silent.

"I dunno, that's what it looked like when I first walked in. He sure turned around really fast, and he seemed kind of flustered. And a week or two ago, he was staring at you all the time. I thought it was kind of creepy." She wrapped her arms around herself. "He's not bothering you, when no one else is around, is he?"

He laughed, sincerely, although he had to appreciate her concern. "You don't need to worry, he's not bothering me. You must've just startled him earlier, I guess, he was asking me for a cup of coffee."

She sighed in relief. "Okay, then. I must have been imagining things."

"Probably. Thanks for having my back though," he said with a smile. "Lemme know if anyone ever bothers you like that, and I'll do whatever I can, okay?"

"Of course!" she said happily, "But yeah, I should get back. See you later!"

"See ya." Sans waved goodbye as she headed down the stairs, then turned around and planted his forehead on his desk. "Oh my god, that was close," he whispered. At least she believed him, and he hadn't needed to lie, much. Not that she or his other coworkers could _never know_ , but it was going to be much easier if they didn't. _Oh wait, doesn't Larkeet know?_ he thought. _Good thing she hasn't told anyone else_. He heaved a sigh of relief and pushed himself away from the desk, and down the stairs toward the elevator. It was in use when he got to it. _Gaster must be on his way up._

Sure enough, the doors opened up a moment later, and Dr. Gaster stepped out. "Oh, Sans!" He closed the distance between them and wrapped his arms around the skeleton's shoulders. "Listen, I'm sorry, but I'm probably going to be spending the rest of the day with Asgore, I need to make sure he's okay." He pulled swiftly out of the hug to look Sans in the face.

"I uh, okay," Sans responded, eloquently. "Is everything alright? Did the human injure him, or something?"

"Probably not, but he's... I suppose you must have been very young the last time a human came through the underground, but he didn't leave the castle for over a week afterward, and things were a bit of a mess." Gaster shook his head. "I guess killing someone, no matter how justified, can take its toll on you. The sooner he's back on his feet, the better for us all. I'm sorry. If he's already being taken care of, I'll come right back and help you move the blast cannon. Until then, get as much done as you can, we need to make sure it's ready before another human has the chance to come down here."

Sans nodded. "Alright, I'll do what I can. Um, take care, ok? Tell Asgore I said 'hi', or something." He looked away. This sounded pretty important, and his feelings on the matter weren't going to get in the way.

Suddenly, Gaster grabbed his chin and pulled him into a deep kiss. Caught off guard, Sans gasped before leaning into it, enjoying it. "Thank you for understanding," the doctor whispered, gently pulling away. He smoothed out his jacket and stood up straight. "Alright, time for me to get going. I'll see you later, be safe."

"Yeah, you too." Sans said quietly, as Gaster marched out the front door.

Maybe he was still in shock from being kissed so suddenly, but despite knowing who Gaster was going to go spend the day with, Sans didn't feel the clutch of paranoid jealousy he had experienced just a few days ago. He wasn't about to go looking for it, but it was strange not being overtaken by concern. He decided to shrug it off and take it as a blessing. After all, Gaster had made it pretty clear over the course of the weekend that he wanted to be with Sans.

He couldn't help but grin thinking about it, as he rode the elevator down to the lab proper.

* * *

 

Gaster had no problems getting into the palace, despite the commotion. Folks figured he was there on important business and made way for him to pass, and the guard knew who he was. Once he arrived at Asgore's home, however, Captain Undyne blocked his way.

"King Dreemurr's not taking any visitors today," she said curtly.

"Captain, please let me pass, I'm here on business."

"He's especially not seeing anyone on business matters." She folded her arms and stared him down.

"I'm his friend, Undyne, I'd like to see how he's doing."

"Yeah, I'm his friend, too. He talks about you sometimes, you know that?" she asked, sneering. "Especially how hard you are to get a hold of, and how rarely he sees you. I think he tried calling you four times this morning. Sure took your sweet time showing up though huh?"

Wordlessly, Gaster pulled his phone from his pocket and dialed Asgore's number. He held the phone to his ear and held eye contact with Undyne as it rang.

Once, twice, Asgore picked up on the third ring, with a sullen "Hello?"

"Ah, Asgore? It's Gaster, I'm told you tried to call earlier, but my _phone was dead_ ," he said pointedly, "I'm outside your home right now, may I come in?"

Undyne huffed and rolled her eyes, but behind her, Asgore's front door opened, and he peeped his head out. "Please, friend, come in. I am happy to see you," he said, with a sad smile. "Undyne, let him through," he added.

She grudgingly obliged, and Gaster smirked as he closed his cell phone and stepped past her into the king's home.

The first thing he noticed upon entering was the atmosphere, a much cooler temperature than usual.

"Please, sit down, I'll make us some tea," said Asgore, as he lumbered toward the kitchen.

"Allow me, actually," Gaster insisted, placing a hand on the king's arm to get his attention. He turned his gaze to the empty fireplace beside them. "Why don't you get a fire going? I'll fix us some tea."

"You're my guest-"

"And I came here to make sure you are alright. Have you eaten? No? I'll fix some snacks, too. Please, sit."

Asgore grumbled incoherently, but took a seat by the fire as Gaster made his way into the kitchen to set water boiling and prepare something easy on the stomach. Peanut butter sandwiches would probably do the trick. He tried infusing them with healing magic, but his healing magic was honestly garbage, and he knew it wasn't going to do much. _Still_ , he thought, _Asgore needs whatever help he can get._

He brought the sandwiches out, then the tea, once the water was ready, and sat down on another chair in the living room, facing Asgore.

The king took one of the small sandwiches into his massive paws and stared down at it sadly.

"Do you want to tell me what happened?" Gaster asked, slowly.

Asgore shook his head for a moment, before closing his eyes and nodding. He looked like he was about to cry. "I guess you may have already heard, but last night, a human made its way through the underground, all the way to the castle, before they were spotted. One of my guards alerted me to their presence, and I confronted them, and took them down immediately." He brought the sandwich to his mouth and took a cautious bite, chewing slowly.

"What? That's your official story. Tell me what actually happened," Gaster demanded, gently. "Why didn't you apprehend them and keep them contained so I could examine them?" He watched Asgore flinch at this. "Hell, for some reason, none of your scientists have ever gotten their hands on a live human specimen, perhaps we could have learned something-"

"They were so _frail_ ," Asgore croaked, his mouth full of sandwich. He took a moment to finish chewing, then swallowed and continued, tears glistening in the corners of his eyes. "I didn't mean to kill them, Gaster, I didn't. I believe they were close to death when they arrived... I just- I had second thoughts about taking them down, and I couldn't help it this time. There was nothing I could do, they collapsed and..." The tears broke free from their gates and came spilling down his cheeks.

Gaster stood up and made his way over to Asgore, rubbing his arm gently to console him. He watched the king cry harder than he'd ever seen him cry before, and stood by him for what seemed like forever, until the tears died down and the king could speak clearly again.

"I'm sorry, I just, I don't know how to feel about this. The child... they've _all_ been children... it looked so sickly. I would have sent them to you had I been able to apprehend them properly, but... well, I don't know how much you can learn from them now, their soul has already left their body."

"Shhh, that's not what's important right now," Gaster urged him trying desperatly to quell the pang of guilt inside himself, "I'm sorry for acting like it was an interrogation, that' wasn't why I showed up here."

"Why are you here?" Asgore asked, looking up at him.

"I'm here to cheer you up. Tell me how I can do that."

"Your company is enough to lift my spirits, friend."

"But-"

"Really."

That wasn't good enough. Gaster couldn't just do nothing and say he was helping. "How about I help you with your gardening today?" he offered.

Asgore perked up. "But I like gardening," he protested.

"And I don't know half of what I'm doing out there, which is why you should accompany me, and we can get it done together."

The king hummed lowly. "Oh, alright," he relented, smiling, "I will grab a spare watering can, meet me out there."

"Deal!"

Gaster sighed in relief once he was out in the garden, out of earshot. He felt a little bad about dragging Asgore out to do things when he wasn't feeling well, but leaving him inside to brood and stew about what happened wasn't going to help anything.

He stole a glance to the doorway past the throne, where his crew was probably working diligently, while he took the day off. "Sorry," he muttered to them, all of them, "but this is important, too." He could work over the weekend to make up for what he missed today, but he wouldn't be able to make up for skipping out on Asgore when he was down.

The king entered the garden, carrying two watering cans and a few tools, and placed them by Gaster's feet. The two set to work, and within several hours, had everything watered and trimmed and taken care of. In all honesty, it probably took Asgore the same amount of time to do it by himself, but Gaster had questions about each plant that Asgore was happy to answer in detail.

By the end of it, they were both a bit worn out, but definitely in better moods. They leaned against one of the walls of the throne room, surveying the results of their hard work.

"It looks so wonderful and lively," Asgore marveled, "you have a knack for this."

Gaster chuckled. "if you say so. I wouldn't mind coming over to help more often, it's... it's almost therapeutic, in a way."

"It is," the king agreed, "I love it." He quietly turned his gaze to Gaster's face before speaking again. "Thank you, Gaster,"

"Of course, I'm-" he was cut off by the gentle feeling of Asgore cupping his shoulder. His whole body stiffened under the touch, and his heart raced. Panicking, he blurted out the first thing that came to mind: "Asgore, I'm seeing someone!"

Asgore pulled his hand back, and stared at Gaster with a mildly shocked expression.

They stared at each other for what felt like an eternity, Gaster's teeth clenched in trying to control his heart rate, and Asgore looking like he was regretting even having hands. Finally, Gaster broke the silence with an explanation.

"It's been a few weeks now, I didn't tell you because... because I was worried it wasn't germane, and I didn't want to upset you." He looked away. "Like I"m probably doing right now."

"You haven't upset me," Asgore assured him. Gaster looked back up in time to see a dark blush spread across the king's face. "Had I known sooner, I would not have been so... well, _forward_ , but I am happy for you." To his credit, the smile he gave Gaster looked entirely sincere, if not a little sad. "

"Thank you for understanding," said Gaster, hanging his head.

"Although, I can't help but wonder. These last few weeks... is it one of your coworkers?"

Gaster felt an icy chill overtake him. "What?" he asked, as innocently as he could.

"Well, one of them sure seemed to have his eye on you, and he didn't look to happy when I was there. I did wonder briefly if..." He shook his head gently "Well, I can't say I disapprove, you and Professor Wickett have known each other for quite some time now, haven't you?"

"Wh-" the ice in his veins was immediately replaced with bile. "Wickett? Really?!" he demanded, stomping his foot. "First Marlick, now Wickett, does everyone really think I have such terrible taste?!"

Asgore laughed in loud, joyous bleats. "What?" he asked, when he eventually caught his breath. "What's wrong with that? He's not so bad."

Gaster folded his arms and scowled.

"Ha ha, well, I think he's alright."

"Then you date him, and leave me out of it."

Asgore laughed even more at that, and it was hard for Gaster to stay upset with infectious laughter like that echoing around him. He smiled and leaned back against the wall. Asgore didn't seem intent on pressing the issue of his new lover's identity, and he couldn't say he wasn't grateful for that, but part of him felt guilty for wanting Sans to remain a secret.

"I am grateful you showed up today, Gaster, thank you."

"Of course, any time," Gaster responded, without thinking. "Wait," he corrected, "I mean, any time that we're not tremendously busy, the two of us. Which, for me, may not be for a while."

Asgore cocked his head to the side.

"I've moved the deadline for the cannon's completion to ASAP. So, after today, my team and I will be a bit busy."

"Oh. Are you really going to rush yourselves, like that? Why not take the time to do things right?"

"Things will be done correctly, don't worry. I just don't want to give fate the chance to throw any more... surprises our way."

Asgore thought deeply for a moment before responding. "Very well," he said, solemnly, "I place my trust in you, thoroughly."

"Thank you," the doctor said, bowing his head.

"That aside, are you hungry? Because I have some leftover turnovers in my fridge and-"

"I always have time for turnovers," said Gaster eagerly.

 

**Notes for the Chapter:**

> I imagine Asgore's laughter is like honey pouring over buttercups, thick and sunny and sweet.  
> :-3


	37. Let's chat.

**Notes for the Chapter:**

> Okay, so tumblr user trisaffritops has been a busy little bee!  
> [They've drawn fanart from last chapter,](http://trisaffritops.tumblr.com/post/146981867741/made-for-a-fic-ive-been-keeping-up-with-i-think)  
> [from chapter 14](http://trisaffritops.tumblr.com/post/147006209591/are-you-leaving-gaster-asked-he-was-leaning-up)(nsfw)  
> AND  
> [have threatened to make a comic based on this fic!!](http://trisaffritops.tumblr.com/post/147177893236/figsheep-its-underway-im-starting-the-comic) (my applause and admiration because wow)  
> Check out their cool, nsfw blog if you're old enough! (if you're not old enough i have to wonder what you're doing here )

Gaster had one more stop before checking up on his employees. Luckily, the newfound shortcut system allowed him to travel to the edge of Snowdin Forest quickly and stealthily. He marched through the deep snow, following the trail of footprints the human had left behind, until he came to the large door at the edge of the woods that separated the ruins of Home from the rest of the underground. There was no knowing if his friend Toriel was still there, but it would be worth it to at least knock and find out. He summoned a magic hand and rapped the door as loudly as he could, and silently he wished to himself that it hadn't been over two months since his last visit with her.

He heard a shuffling on the other side, but nothing else. "Toriel, is that you?" he called out.

"Oh, Gaster, thank goodness, it is you!" Toriel exclaimed. "I have been hoping to hear from you all day! Have you... have you seen or heard anything unusual today?"

Gaster frowned. "You mean like the human footprints trailing from this very door?"

She was silent for a while. "Do you know what happened to the human? Where they are now?"

"I am afraid they encountered King Dreemurr, and are no more, madam," he said sadly, leaning against the door.

"Are you sure?"

Gaster's heart ached for her. "He told me the news himself."

"I see." he heard a quiet sob. "Thank you for letting me know."

"I'm sorry, Toriel."

"No, it is alright. I should have expected as much, really." She laughed dryly. "This happens every time. This one snuck out while I was sleeping, I'm sure of it. They were ill and I thought they would gladly take the time to rest and get better before trying to venture out," she said wistfully, "That is what I get for underestimating a human, I suppose."

* * *

  
"Sans!" Gaster called as he passed through the door to the barrier. Their workday had ended an hour ago, but he was pleased to find the young skeleton still toiling away.

Sans looked up and smiled as the doctor strode over to him. "Oh, hey Gaster."

Gaster closed the distance between them and leaned down to give Sans a quick, rough kiss on the mouth. "Hey, yourself," he said lowly. There was a loud whistle and a whoop from behind him.

"Woooo! Can't believe I get a free show!" Called Larkeet from across the room. Gaster looked to her helplessly, then back to a blushing Sans, and shrunk in on himself.

"I'm sorry," he said quietly, "I should have checked first to make sure we were alone."

"Aw, but where's the fun in that?" she chirped. Gaster shot her a nasty look and she stuck her tongue out to him and winked.

"It's cool," Sans assured him, shrugging, still flushed. "What's up, you done with Asgore for the day?"

"I am, in fact. I wanted to check up on you, and your work." He glanced around them. "Is it just you and Larkeet staying over?"

"I told June she could go home early if she went to check on Wickett first," said Larkeet, "We hadn't heard from him all day and I was kind of worried, because of the uh, you know, human and all that. Turns out he tried to call in sick this morning, but no one answered. He's alright, at least. Just zonked out on some really strong painkillers."

Gaster winced, realizing that must have been who he hung up on when he first woke up.

"Things have been going pretty well over here," Sans said, "got the whole cannon moved over like it was nothing. Now I'm getting started on assembly. Figured I'd stay a little late tonight, I'm kind of in the zone."

"Would you mind terribly if I stayed to help you?" Gaster asked. Sans shook his head with a smile.

"Yeah, don't mind _me_ , it's not like _I_ need help," Larkeet called over her shoulder. Gaster rolled his eyes and turned to face her. "I'm kidding!"

He sighed and turned back to Sans, who was chuckling quietly.

"Thanks for making me your favorite," the skeleton whispered.

Gaster gave him a silent wink and grabbed the blueprints for the cannon to look them over.

"So," Larkeet continued, "How is the big guy? Was it as bad as last time?"

"No, I don't think so. I got him out of the house, at least. But this will probably take a toll on him, how could it not?"

"Yeah, I can't even imagine having to do something like that, and I'm kind of a bitch." She sighed.

"Yes, well," Gaster mumbled.

" **I heard that.** "

"So, he's gonna be alright?" Sans asked.

"He'll recover, in time," said Gaster. He thought to himself for a moment, then leaned in closer to Sans to whisper "I told him, by the way. About us. Sort of."

"What? Really?" Sans whispered back, his face turning flushed. It was unnecessarily adorable, and Gaster wished he could pull his eyes away to focus on the task at hand.

"I told him I was spoken for, at least. I should have mentioned you by name, I'm sorry."

"No, don't be that's... heh." Even though Sans looked away, Gaster could see his grin widening. "Thanks," he whispered.

"Oooh, watch out Sans!" Larkeet called from right behind them, causing them both to jump, "He's telling his ex about you, next he's gonna ask to meet your folks."

He and Sans looked at each other, and as Gaster grimaced, Sans burst out in laughter. Larkeet cocked her head to the side as she pulled a pair of pliers from her toolkit.

"He met them a long time ago," Sans said with a grin, "maybe we're doing this out of order, eh, Doc?"

"Is that so?" she asked.  
  
"Yeah, you probably missed the broadcast on Sunday, but my mom interviewed him over the radio? She had a bunch of questions about the cannon. They hate each other though, it was beautiful. Shit, I think they were going to air it again today, but with all the _actual_ news going on, maybe they won't now."

"Oh man, I'm sorry I missed it! But hey, if those two things are out of the way, all that's left is for him to propose to you publicly at a really inconvenient moment!"

"Doctor Larkeet, you are **free** to **leave** at **any time!** " Gaster growled. Despite himself, he could feel heat rising to his cheeks. He glanced over to see Sans grinning widely at him, which worsened his embarrassed state.

"Coulda told me that two hours ago!" she chirped, tossing her pliers back into the toolkit, "But yeah, I'll give you two _lovebirds_ some privacy, if that's what you need. By the way, project disco is pretty much complete. Just make sure everything's tidy and refasten the cover-plate."

"Wait, you're finished?"

"Sure am! And I'm taking two hours off tomorrow morning so I can attend my kid's science fair. Toodles!" And with that, she was out the door, leaving Gaster, Sans, and the cannon by the barrier.

Gaster rolled his eyes as she went. "Good riddance," he mumbled, "Well, I suppose that just leaves us to-" He was cut short as he felt a tug at his coat sleave, and he turned to find Sans staring at him with a wide, lopsided smile. He smiled back and allowed himself to be pulled into a quick, tender kiss.

"Heh, sorry," Sans whispered as he pulled away, "Just had to uh, express that real quick."

"I'm not complaining," said Gaster, "But I really did come here to get some work done. If you stay and help, maybe we could go home together later?"

"Yeah, that sounds good. I've uh, got the bottom half arranged, and most of it put together. All of the screws and bolts are labelled with which parts they go to, and... maybe we can chat while we work?"

Gaster pulled Larkeet's toolkit closer to himself and began to dig through it, looking for wrenches. "Of course, what about?"

"Well, I guess I'm officially your boyfriend now?" Sans waited for Gaster's nod before continuing, "And I don't even know what kind of music you like, or what your favorite flavor of ice-cream is, and I think that's a travesty."

Gaster found himself chuckling at that. "I don't know yours either, so if you want to know, you'll have to tell me yours first." He patted himself on the back for that, what an excellent way to stall while he thought about his answers to questions he never thought he'd need to answer.

They chatted back and forth for the rest of the evening, until Gaster grew tired. He learned so many trivial details about Sans that night, and each one was secretly a treasure.

**Notes for the Chapter:**

> I ALMOST FORGOT TO ADD  
> Either next chapter or the chapter after is going to be smutty, because I can't help myself, but they'll both be posted right around the same time, soooooo just check the beginning of the chapter for a warning if that's what you don't want to see.


	38. Turn it on, turn it up!

The crew met Dr. Gaster in the lobby of the lab the next morning, patiently awaiting his orders for the day.

"Alright, everyone. We're closing in on what might be our final days underground. I want you all to focus, and work diligently to make this happen. Dr. Larkeet, I need you to triple check the core-"

"I'm leaving in three hours, sir," she cut in.

"Which will be more than enough time to go back to the core and make _sure_ they're ready for the extra load, check and check again to see that everything's properly connected and ready to go. Three hours is plenty, and tell your son I wish him the best."

"Alright, thank you."

"Professor Wickett, I'm glad to see you're doing better. I've arranged for you to be escorted back to the mausoleum. Unhook an oscilloscope from one of the other human souls, and hook it up to the new arrival. The three we've been monitoring have all been similar enough, the resonance of this soul shouldn't be too far off, but if it is, I need to know immediately."

"Roger," Wickett said.

Gaster nodded. "Juneborg? Sans and I nearly finished assembling the cannon last night. Once complete, it's ready to be hooked up to the power source at the castle. I'm sending him with you as a safety precaution. There is an immense amount of electricity running through that power port, and if anything should happen, I don't want you alone. Give me a call when you get done, and I'll be there. I need to make a few adjustments to the tuning program, and allow it to utilize that extra power."

"Should I call the lab, or your cellphone?" asked Juneborg.

"My cellphone. Sans has the number, another reason he'll be accompanying you."

"Yep." Sans agreed.

"Okay, then. Are we going to power it on today?"

"Luck willing, yes. If everything goes as planned, we'll power it on today, and fire tomorrow. If not, we'll be working the weekend, and we'll keep going until it works."

"What?" Wickett grumbled, "I'm not going to work the whole weekend and then just keep going, Gaster. How many times do I have to tell you? I've got a life outside of this damn job."

"Then we'll get it right on the first try," Gaster stated simply, "I want to thank you all again for your hard work, and all of monsterkind will be thanking you if we succeed. I won't be unreasonable and deny you all your free time, but if worse comes to worst, we may need to stagger our days off, so that all of us aren't gone all at once."

The scientist groaned collectively.

"What about Alphys?" Sans asked.

"She unfortunately has finals next week, and probably won't be able to join us for this."

Sans rolled his eyes. "Heh, of course."

"Does anyone have any other questions?" Gaster asked, lacing his fingers together.

Shrugging and mumbling rolled through the lot of them in response.

"No? Alright then, let's get to work! Remember, the sooner this cannon is complete, the sooner we'll all be out of here!"

Larkeet sighed and made her way for the door. Wickett followed suit. Gaster turned on his heel and made his way toward the coffee machine, rubbing the side of his head and groaning.

"You ready to go, Sans?" Juneborg asked, turning to leave.

"Just uh, just a sec? Wait for me by the door, and I'll be right out, I need to ask Gaster something."

"Oh, alright. Don't be too long, okay?"

"Yep." He headed for Gaster and the coffee machine, but waited until June was out the door to speak. "Hey doc, I wanted to ask you about something."

"Hm?" the doctor replied, with a mouth full of coffee and mug.

"Can June and I just take a shortcut through the void to get to the castle?"

"Oh no, absolutely not." Gaster shook his head. "No no no. Sans, she's only half organic, the rest of her is practically an electronic device. I won't risk her shutting down." He set his mug down on the table next to him. "No," he added again, for emphasis.

"Okay, okay, I get it. That's actually... shit, I didn't think she was actually electronic, I figured she just had a metal exoskeleton."

"I'm afraid not."

"Huh."

"Indeed."

 

"So uh, you look a bit tense, with all this going on, Doc."

Gaster laughed softly. "I certainly am. It's nervewracking, this being the final stretch."

"Migraine?"

"It's building, yes."

"Shame. Well, if you need my help with anything tonight, or maybe just want to preemptively celebrate our freedom from this magical prison, let me know, okay?"

Gaster smiled. "I'll think about it." He reached for Sans's shoulder, and the skeleton tensed for a moment, only to feel a small tug as the doctor plucked away a loose thread.

 _Man, these labcoats are shoddy_ , he thought. As he was distracted by that thought, Gaster was able to swoop in for a quick peck on his cheekbone.

"Go on, get to work," the doctor told him, "And be safe."

"Roger that." Sans gave a mock-salute and marched toward the exit, grinning. Hand on the door, he paused. "By the way, Gaster? I found some weird little audio-device plugged into the wall near the supply closet yesterday. I left it alone, in case you were using it for anything." He winked and slipped out the door before Gaster could respond.

"What's with that look?" June asked him as he came out.

"Look? Nothing." He willingly relaxed his face, letting his smile slack a little.

" _Sure_. Let's get going then."

They didn't talk much on the way to the castle; June was content listening to the radio, and Sans was content letting his thoughts wander.

"So," she asked him later, as he held the final plates of the shell in place for her, "what are your plans, for when we reach the surface?"

"Don't you mean 'if'?"

"I'm trying to be optimistic, here. Don't tell me you haven't given it any thought."

He laughed. "No, you're right. I've thought about it a little. It's hard to imagine what life would be like on the surface, without knowing what the surface is actually like. I doubt human movies are realistic, you know?"

"Do you think we'd keep our jobs?"

"Hard to say. What would the royal scientists even do if the obvious goal of 'bringing down the barrier' disappears?"

She shrugged. "If the humans declared war on monsterkind again, we'd probably get stuck building a bunch of weapons. Granted, I hope it doesn't come to that, but hey, this is the job I signed up for."

"What would you rather do?"

"Help them build spaceships."

"Sounds like a lot more fun than cannons." Sans sighed as he thought about life on the surface. He realized after a moment that most of his thoughts centered around Gaster, and whether they'd still be together with so much going on around them. He shook his head and refocused his thoughts to his family. Didn't Papyrus dream of driving a cool car? Maybe he'd learn to drive with his brother.

Maybe he'd take Gaster on a road trip, and the two of them could explore the world above.

* * *

 

Once Sans and Juneborg had finished with their work, Gaster rushed over to the castle with the controller for the cannon, the tuning program having been installed on a more portable computer. Larkeet arrived shortly after him, proudly proclaiming her son's victory in the science fair. "Ruffle won the category for his age group, he's going to be a scientist just like us someday!" She exclaimed. They had all congratulated her for raising an upstanding child, then it was back to work.

With the three of them working, it took no time at all to set up.

Gaster took a deep breath, pausing with his finger over the power switch. "One," he counted, "Two," another deep breath, "Three!" he hit the switch and the sound of electricity rushing into the cannon's power supply filled the air.

All three of them sighed in relief. With the cannon functional, the hardest part was over.

He powered the machine back off, and waited for the power in it to die back down before turning to his team. "That's it," he told them, "tomorrow's the big day. I'll let Asgore know we're firing the cannon for real. Sans, I don't know if you can get a hold of your mother, but I think the citizens of the underground would appreciate a heads up. They might experience some minor interference with their electricity service tomorrow, when we pull the trigger."

"I'll let her know."

"Should we inform professor Wickett that we're good to go?" Juneborg asked.

"I'll find him and tell him. You and Larkeet are free to go home, we'll all meet here tomorrow morning. Oh, Sans, you can leave, too, I just need your help with something first." He ignored the inconspicuous wink Larkeet shot him.

"Gotcha."

Gaster walked over to Sans, and waited patiently until Larkeet and Juneborg were out of sight before wrapping his arms around him. "I'm so nervous," he whispered, resting his chin on top of Sans's head, "This really could be our last night as prisoners here."

Sans returned the embrace, squeezing Gaster tightly. "Sounds like it. Are you excited?"

"I am. Are you?"

"Definitely... Hey, Doc? What do you want to do when you get to the surface?"

"I haven't really thought about it," said Gaster calmly. This was a lie. He had thought about it plenty of times. But the last time he had given it any serious thought, there had been no one else in his life. Plans change.

The two of them stayed quiet for another moment, enjoying each other's closeness. Finally, Gaster pulled away. "We should get going," he said, "How about... you go round up Wickett, I'll call Asgore, and the two of us can meet back at my house?"

"Sounds like a plan to me," Sans replied, shrugging.

Gaster leaned down and kissed him gently, oblivious to the figure approaching them from down the hall.

A loud sigh of disgust sounded from behind them, and Gaster quickly pulled away to find Wickett standing there scowling.

"Should have fucking guessed it," he groaned.

 

**Notes for the Chapter:**

> Okay, next chapter's gonna be the dirty one, don't let the title fool you!


	39. Holding Hands

**Notes for the Chapter:**

> Okay, THIS is the smutty one. Skip if you like.

Sans lay trembling on his back as Gaster smiled down at him, holding him down by the femurs to keep from squirming or kicking away. He gripped the pillow above his head, and clenched his teeth to keep from moaning too loudly at the intense sensation of Gaster's magic on his own.

The idea of Gaster holding hands with Sans's crotch had been hilarious when it was still floating around in his head. In actuality, it was almost too much to bear. The fingers of one of Gaster's magical hands now laced between his own, and held him with an iron grip that only tightened every time Sans started squirming. He drew in a loud Gasp and tried to squeeze his legs together, to no avail.

"Is this too much for you?" the doctor asked, above Sans's moaning, "Say the word and I'll let go."

"F'you can't feel that?" Sans rasped.

"Not as well as you, apparently. I can't feel much of any sensation through my magic."

"Lucky me, then." Sans laughed dryly and stretched his feet out until they reached the front of Gaster's pants. He rubbed his toes in circles over the large bulge in the center, listening for a reaction from his lover. "How about now?"

Gaster chuckled. "Mmm, yes."

Sans felt the grip on his hand tighten just slightly, sending a shockwave of pleasure through him that forced a whine from between his teeth. He clenched his eye sockets shut and tightened his own grip on Gaster's hand, not that the doctor could feel it, apparently.

"You know, Sans? I have to say this might be the strangest thing I've ever done in bed with someone." Gaster slid his hands up San's legs, toward his pelvis, and stroked the skeleton's hips with his thumbs.

Sans let go of the pillow above his head and brought his own hands down over Gaster's. "Yeah?" he asked with a smile. "Is 'arm-wrestling someone at the crotch' really at the top of your list?"

The doctor chuckled. "When you put it that way, most definitely. He finally loosened his grip on Sans, just a little. "What about you?"

"Yeah, I've probably done weirder things." He sighed in relief as Gaster's grip on him loosened even more.

"Such as?"

Sans took a moment to catch his breath. "I said 'probably'. Can't think of any examples off the top of my head, but I've been with lots of different kind of monsters, so I guess it depends on your definition of _weird_."

Gaster's hand let go of his completely, and he worried for a moment he had upset the doctor, until he felt the gentle strokes of fingertips over the palm of his genitals. "Nothing stands out?" Gaster asked with a smile, leaning over him.

Sans arched his back and brought his hands back over his head, losing himself in the pleasant, gentle sensation. "Honestly? Out of all the times I've been with people, the thing that stands out as the most different from the rest would be... the last time we were in bed together."

The doctor pulled back slowly, releasing his grip on Sans's legs. His magic dissipated. "What was so strange about that?" he asked, cautiously.

"I mean it wasn't bad," said Sans, sitting up quickly. He let his own magic dissipate as well, afraid he had spoiled the mood. "It was just so... _intimate_. I think that's the closest I've been with anyone. Ever."

"I may have gotten carried away," Gaster whispered, looking down.

"But I wasn't imagining it, was I? You shared yourself with me. I felt you, _your soul_ , I think." No response. "I gotta say, I liked it. Gaster," Sans reached forward to grab the doctor's hands, "that was the most amazing thing I've ever felt."

Gaster was flushed, and wouldn't look Sans in the eye. "I'm glad to hear that," he said softly.

Sans got up and crawled forward, until he was sitting in the doctor's lap. "If you'll let me, I'd like to share myself with you, too," he whispered, leaning forward until their foreheads touched. He could feel the heat radiating off of Gaster's face.

"Feel absolutely free to," Gaster replied, finally glancing up at him.

"Okay, except," he draped his arms over Gaster's shoulders, his heart racing, "I don't know how... to do that."

Gaster laughed, smiling gently. "It's not really something I can tell you. I'm sure you'll figure it out."

Sans kissed him deeply, met with no resistance. He held him close, and was embraced in turn.

He could feel Gaster, not like last time, but still intense, but he had no way of knowing if Gaster could feel him.

"Can you," he panted, pulling away from their kiss slowly, "lay back for me? Please?"

"Certainly."

Sans had to figure this out on his own. He ran his hands slowly up Gaster's abdomen, up his chest and to his collarbone, before bringing them even more slowly back down. He rested them on the button of the doctor's trousers, and flicked his gaze up for a sign to continue. With a nod of approval, he undid the button and pulled the trousers and underpants down slightly, allowing Gaster's erection into the open air.

Gaster closed his eyes and leaned back, gasping a little as Sans touched him. The skeleton rubbed his palm gently up against the underside of the shaft, and watched Gaster wince slightly before his face relaxed. He watched the rise and fall of his boyfriend's chest as he gripped the base of his erection, stroking slowly upwards.

Sans felt a swell of affection in his own ribcage, and wondered if that was how it starts. He allowed his magic to form at the front of his pelvis, a long, thin tendril that wrapped around Gaster's member as his hand released it.

The doctor opened his eyes and glanced down quickly at the new sensation. Sans grinned back at him and gave him a few slow strokes with the winding tentacle, relishing the little whimper that sounded from Gaster's mouth as his eyes rolled back and his head dropped.

He situated himself over Gaster's chest, not minding at all when the doctor began to thrust up into him slightly. The tentacle curled and coiled, stroking the tip of Gaster's cock, squeezing around the base. He reached out to hold one of Gaster's hands, and laced their fingers together, gripping tightly. He wanted so badly to share himself with Gaster, to let him feel what he felt, when he caught him sleeping at his desk, or held him close. He stretched himself forward to kiss Gaster on the mouth, but couldn't quite reach.

Gaster must have picked up on this, and curled forward slightly, kissing Sans passionately and moaning into his mouth as the tendril squirmed around his member. Sans kissed him back, hard as he dared willing and hoping and praying that Gaster could _feel_ him, could understand how he felt, the rush of affection and longing that took over him, the desire to hold on and never let go that swept over his bones and made him feel like he was overheating, sinking when the doctor was near.

The moment was over as Gaster gripped him tightly, hips bucking upward, and he felt hot spurts of cum coating his spine and lower ribs. He pulled back slowly, allowed his magic to dissipate, eyes closed to keep the tears from forming as something he'd only ever dreamed of sharing with someone slipped away. He turned his face up for a moment, took a deep breath and steadied his expression, so he could at least look Gaster in the eye with a smile.

When he glanced back down, Gaster was beaming up at him with tears in his eyes.

"Wh- are you okay? Did I-"

"Yes," Gaster cut him off, "Yes you did. _Sans!_ " he pulled him down into another kiss, holding him tightly, and Sans allowed himself to be held, wrapping his arms around Gaster as tightly as he could. He had done it, shared himself with someone, bared his soul for someone. The tears came, not many and he let them flow as Gaster held him and kissed him.

"Thank you," he whispered.

Their fingers laced together, and Sans fell asleep on Gaster's chest.

 

**Notes for the Chapter:**

> I uh, got a little emotional while writing this. This is why we don't drink and write smut, kids.
> 
> "So, what IS the weirdest thing you've ever done in bed with someone?"
> 
> "Well, it wasn't in a bed, for starters. You ever been with someone who can dissolve in water?"


	40. Three... Two... One!

**Summary for the Chapter:**

> Are they finally firing that damn cannon after thirty-nine whole chapters?? Golly!

**Notes for the Chapter:**

> For those of you who have been skipping the smut, and therefore did not absorb the last chapter- kind of a little thing you might have missed: Sans and Gaster have 'made love' (not in so many words) twice now, and each has kind of... shared his soul? with the other. Not like, an actual, tangible, upside-down heart thing, just... the feeling of it? Of their bare selves, their essence. I don't know what I'm doing, I just got really emotional while writing and put it in there. Neither has used the 'L' word, though.   
> They won't, yet. I won't allow it. 
> 
>  
> 
> Yet.

The next morning was tense from the word _'go'_. Waking up at Gaster's for what might be the last time? Surreal. Breakfast? Solemn. Getting ready for work? Down right somber. If success meant freedom, their lives would change drastically by the end of the day, he and Gaster both knew that. There wasn't much to talk about, otherwise.

Verdana had been ecstatic. When Sans called her at the station, she congratulated him and asked him all kinds of questions about what they were doing. But towards the end of their call she got quiet, told him she loved him no matter what, and wished him luck. Everyone was like that. His coworkers, Asgore, guards around the castle, everyone chatted excitedly about the surface, about how today might go down in history, about their plans for the hypothetical future once they were free. They all sounded so happy and hopeful, but then the conversation would lull, and the ensuing silence would drag out much longer than normal, until forcefully broken by switching topics.

Everyone was full of hope, sure. But it was a cautious, restrained hope. One they could easily take back should things not work out well. They were all used to hoping like this.

Sans was so lost in his thoughts that he failed to notice Wickett three feet in front of him, and ended up near knocking him over when they collided.

"Will you watch where you're going?!" the professor demanded, once he had regained his balance.

"Shit, sorry," Sans mumbled, dusting himself off, "I was a little distracted."

Wickett rolled his eyes. "Par for the course," he said, turning away.

Sans reached for the professor's elbow, stopping him. "Hey uh, sorry again about yesterday-"

"I'll tell you one more time, and that's it," Wickett cut him off, dropping to a whisper, "I don't give a shit what you two do in your free time, as long as I don't have to hear, see, or think about it. Do you want details on my love life??"

The skeleton rapidly shook his head.

"Thought so. Now, _focus!_ " He waved Sans off with one hand as he turned away. "And watch where you're going!" he added.

Truth be told, he couldn't focus. He bustled around with the rest of his crew, trying to keep busy, but his stomach was turning and he really just wanted to lie down and sleep through the day, so he could wake up and join everyone else on the surface. The suspense was the worst part, especially now that most of their work was done, and they were just waiting for Asgore.

"Sans, could you go back to the lab and fetch some more safety equipment?" Gaster asked him, tapping him on the shoulder, "Just a few more pairs, for the guards that will be joining us."

"No prob," said Sans with a grin. He stepped out and through the void, focusing on the basement of the lab as his destination. He came out through the storage closet door, and took a moment to stretch and yawn before turning around to grab the spare equipment.

If he had skin, he would have jumped right out of it. Nestled in a mess of cords on the shelf in front of him was the little white dog. Sans staggered back, managing only just not to yell out in surprise. He was met with no reaction; the dog was curled up and sleeping soundly. He pressed his hand to his sternum and sighed in relief, before reaching down slowly for the labeled box on the floor at his feet. When he straightened himself back up, the dog was awake and staring at him, tongue lolling. His pulse raced.

"Hey, little guy," he croaked nervously, "Go back to sleep, okay?"

The dog's tail began to wag slowly, and Sans took a step back.

"Or don't. That's fine. How about you just..." He took a deep breath. "How about you behave yourself today? We're doing our best here, and if we break down the barrier today, that's it, yeah? We'll all be free, even you."

He chuckled dryly as the dog cocked its head to the side.

"So uh, if all goes well today, without any interference on your part, I'll treat you to a game of fetch. That sound good? Yeah, your tail's wagging, of course that sounds good. Just. Be good." He turned and closed the door slowly behind him, hopefully sealing the mutt inside for a little bit. _With any luck, that's one less thing that can go wrong today_ , he thought, as he made his way for the hall.

By the time he had returned to the barrier, Asgore had arrived, and so had Alphys. Sans pulled a pair of safety goggles and some earmuffs out of the box and set it down next to him as the pair of guards accompanying Asgore came over to collect theirs.

"Hey, Alphys, what're you doing here?" he asked, holding out the gear for her, "thought you had school."

"We're mostly reviewing old material to p-prepare for finals." She shrugged and took the gear he offered her, putting the goggles on first. "Anyways, this is a bit more important."

"Yeah, I mean I _guess_ so," he replied with a wink, "Years down the road, though, when folks ask you where you were when the barrier came down, you're gonna have to tell them you were playing hooky."

"I'll tell them I got to watch it happen," she said, rolling her eyes, "G-go put on your safety equipment, Dr. Gaster says we're going to start in ten minutes."

"Shit, already?" He pulled his goggles and ear protection from his labcoat pockets, and made his way over to Gaster, who was sitting over by the controls, nervously drumming his fingers against the top of the monitor. Sans came up behind him silently and placed one hand on the doctor's shoulder, startling him out of whatever deep train of thought he had been lost in.

"Oh, Sans. Are you almost ready? We've got less than ten minutes before we're firing the cannon."

"I'm ready," Sans told him, giving his shoulder a gentle squeeze, "Dont' be nervous about this, okay? We've got this down, and soon all this hard work's gonna pay off, and we're gonna be out of here."

Gaster's face relaxed, and he gave Sans the barest hint of a smile in return. "I know," he whispered, "We'll succeed for sure."

Sans smiled back, and glanced up and over Gaster's head to spot Asgore not fifteen feet away, staring at the two of them with a curious expression. "Right, well, I'm gonna go make sure those guards put their equipment on properly," he said tightly, as he slid his hand down from the doctor's shoulder. Gaster reached out and caught his hand briefly, giving it a quick squeeze before letting go. Asgore was still watching them, and Sans could feel sweat forming on the back of his skull. He glanced up again, just briefly, to find that the king's expression had changed. He looked weary, depressed, but flashed Sans a small, reasurring smile, along with a solemn nod towards them.

"Eight minutes, now!" Gaster called out to him, as he turned away.

Seven minutes later, everyone was in their places, behind the cannon, waiting. Gaster was seated by the controls, watching the screen intently to make sure everything was set correctly. Double checking, triple checking, everything was in order.

Asgore was standing two feet behind Sans, and the skeleton was fighting to keep his breathing even, to not look back. Had he given them his approval just a few moments ago? Sans was dying to know. Just what was that sad look? _Focus, Sans, there's other stuff going on right now,_ he told himself.

"Alright, everyone! Thirty seconds! This is it!" Gaster called to them over his shoulder. "We're ready."

He powered on the cannon and its giant maw slid slowly open as the magic and electricity built up within the machine. Sans's body tensed in anticipation, and he looked around the room quickly to find everyone else in the same state.

Tense.

Alert.

Waiting.

_Ready._

He turned his attention back to the cannon, as Gaster began to count down from ten. The brilliant ball of blue light was building between the machine's teeth, larger and more potent now than it had been during their testing. This was the real deal.

"Three," Gaster called out, "Two! One!"

The beam shot forth like lightning, and it was blinding. Sans's eyes blinked closed on instinct, and in that second he missed the point where the beam actually made impact with the barrier itself. But he couldn't have missed the sound. The grinding, pulsing sound of the barrier trying to resist, dispel, and absorb the enormous amount of electrical and magical energy hitting it was deafening, overpowering his hearing protection and making him wince. The sound grew as the amount of energy grew, and pushed its way deeper and deeper into the forcefield. Electric sparks danced across the surface, and the surface of the barrier itself seemed to ripple and distort as it was bombarded with its own frequency. Still, it resisted shattering. Arcane magic straining, it held itself together.

There seemed no end to it, and Sans was unsure how long the cannon had actually been firing, when the lights in the room around them seemed to flicker for a moment. He looked around, saw Gaster turn back over his shoulder to say something, but couldn't hear it over the roar of the cannon. Next, the beam itself wavered, stuttered, and cut off before resuming, seeming a bit less than it had just seconds before.

Then, everything went dark, and the cannon shut down.

 

 

**Notes for the Chapter:**

> Btw, are there any songs that remind you of this fic, or does this fic remind you of any songs out there? I'm putting together a lil playlist, but I've got maybe five tracks to go in it. They're all songs that have inspired moods or events in the story so far. Well, one of them is for something that hasn't happened yet, but whatevs. If you've got one, please let me know? You can leave it in a comment, or even message me on anon on tumblr.


	41. Blackout

**Notes for the Chapter:**

> Hello, and sorry for the wait! 
> 
> In the past week, a wonderful anon made some wonderful, smutty artwork for the last smutty chapter!  
> http://imgur.com/a/ZaIA8  
> Thank you, Anon! <3
> 
>  
> 
> I thought i'd have more to say here, but i've gotta leave for work, sooooooooo

Sans's eyes strained against the dark, the large streak of light from the cannon still burned into his vision not long after it had ceased. He blinked his sockets several times, trying to clear away the afterimage, and adjust to the light-less room. By that time, the darkness had been interrupted by Asgore's fire magic, which cast a warm, dim light across them.

"is everyone alright?" the king asked. An affirmative murmur traveled around the room.

Sans looked over to Gaster, who had taken out his cellphone and was staring it down and cursing under his breath. "You alright, Doc?" the skeleton asked, cautiously shuffling his way over to where the doctor was standing.

"Cellphone towers are down," Gaster responded sternly, not looking up, "We've got a blackout."

"Doesn't answer my question," said Sans, placing his hand gently on the small of Gaster's back.

"I can't fucking believe this," Gaster whispered. He looked to Sans with a sullen expression before turning to everyone else. "We caused a blackout," he announced, "No worries, we'll do some damage control, and once the core is back up and running, we can try again! We must have just, shorted something out. It'll be fine. Larkeet?"

"Yes, sir?"

"I want you and Sans to go down to the core, and find out if this is going to last more than an hour. If so, show Sans where the emergency lamps are, and have him distribute them. I'll meet you there shortly. Sans, you're free to take the **quickest** route there, but please be safe."

"Roger," Sans replied with a nod. He filed in behind Dr. Larkeet as she turned to leave the room, tuning out the orders Gaster was passing out to the rest of their team. "Hey, Dr. Larkeet, can you close your eyes for a sec?" he asked, reaching for her shoulder as they neared the door to the throneroom.

"Um, why?" she asked, skeptically.

"No reason." He opened up the void and pushed her through, then through again to a doorway somewhere in the Core. He wasn't really familiar with the layout, so had no idea where they were. He felt her feathers puff up under his hand, as she looked around, startled by the sudden change in surroundings.

"What the hell was that?!" she demanded, whipping her head around to stare him down, "Wh- Sans, what the _hell_?! How- Oh, Poma!" she called out, looking up and over his shoulder. He stepped aside so she could push past him and turned around to see a small round silhouette standing in the dim light of the hallway behind them.

"Hello, Dr. Larkeet. We are experiencing a nation-wide blackout. I apologize for the lack of lighting," the sillhouette whispered, clicking softly.

"I noticed," she replied, approaching it, "what happened?"

"We were overloaded. The safety mechanism was triggered. The core has been drained. Everything shut down. We should be back in order by nightfall."

"That long, really?" Sans asked, stepping closer to the other two.

"Yes. Returning all areas to normal will require five hours, at least. Power takes time to build up. And we are scrambling, in the dark."

"Oh, alright," sighed Larkeet, "Dr. Gaster will be over shortly to help get everything set back up. Sans, if we're gonna be down that long, the lamps are a must, not everyone has light-generating magic, after all. I'll show you where they are. Poma, I'll meet you in the control room, okay?"

Poma nodded twice, slowly. A loud click echoed down the halls around them, and the flourescent lighting flickered slowly on. Sans glanced down to find a fat, orange caterpillar in a labcoat on the ground in front of them.

"The core's power has been restored. That should make things easier," said Poma, as it began to slink away.

"The- Poma? The control room is back that way," Larkeet reminded it, pointing off in another direction.

"Of course it is," the caterpillar replied, turning slowly in the direction she was pointing.

Larkeet rolled her eyes and motioned for Sans to follow her down another hallway.

"That's the guy Gaster put in charge of the core?" he asked, skeptically.

"Sure is! Had to put him somewhere, I guess. Glad he doesn't still work at the lab, he gives me the heebie-jeebies." She shivered, her feathers ruffling up again. Sans watched her methodically smooth them out as she led him down to a large red door at the end of a hallway. "Okay, this is our maintenance room," she explained, opening the door, "We've got a few lamps in here, so I can show you what to do with them, at least."

* * *

  
The lamps were large crank-powered floodlights designed to reflect light off the ceiling of the cavern. It had taken an entire hour to set up the twenty-four lamps needed for the entirety of Snowdin, (She'd send other monsters to cover the rest of the underground) and once they were set up, Sans had to go back through to check on them, and keep them charged. It was repetitive work, but at least the scenery was nice, and the locals were friendly.

Larkeet had made him wear a bright orange safety vest, which marked him as someone people should approach with questions.

'What happened?'

'Is the power going to come back on any time soon?'

'Do you need any help with these lights?'

'Weren't they trying to break the barrier today? Did that work?'

'Are we free?'

At least about half of the questions were easy to answer, and he was grateful for the help when it was offered, especially in places where the snow was deep. But when there was no one around, he'd slip through the void to his next destination, and rest against the trunk of a tree, or slump down into a pile of snow.

"No, it didn't work," he'd have to tell them, "We're not free, yet. But knowing Dr. Gaster, we're gonna keep trying until we're outta here." It was difficult, trying to convince everyone who asked that this wasn't anything to get down about, that they would succeed, given time. Not a full day had passed, and they had already fallen back into the same routine of resignation covered up by hopeful words and optimistic pleasantries.

It sucked, to have worked so hard for something, only to have it slip away.

 _But hey_ , he told himself, _mistakes happen, especially in this field! This was a learning experience, and we'll get it right next time. Or, the time after that._

 _And if I find out that damned dog is behind this, I'll be sweeping him into a bucket, and then we'll get it right for sure_.

About six hours had passed before power came back to Snowdin, and Sans sighed with relief when his cellphone rang, and Gaster was on the other end.

"Hey, what's up, Doc?"

"Sans, thank goodness! How are you doing?"

"I'm alright. It's a bit chilly here in Snowdin, but I can't say I'm bothered by it. How about you?"

"Busy, unfortunately. The crew at the core have me all over the place. Do you need some warmer clothes?"

"Heh, I'm good. No skin means no worries for frostbite. But um, are we about ready to wrap this up, now that the power's back on?"

"Well, unfortunately, no. I called to check up on you, but also to ask you to keep the lamps in place for a few more hours, just in case. Waterfall and the capitol aren't back up yet, and Snowdin's connection may be a bit unstable until they are. Just stay safe, and hold tight for a couple more hours, alright? Feel free to take a break too, if you need a chance to warm up or get something to eat."

"Thanks, Doc. I think I'll do just that. You should probably take one, too. You sound a bit rough."

"No promises, but I will try. I'll talk to you later."

"Okay."

Sans stayed on the line a moment longer than necessary before hanging up. There was a silence there, that felt like it should have been filled with something, but he didn't know what. He'd figure it out, later.

* * *

 

Another three hours passed before Alphys called him, passing on a message from Dr. Larkeet that everything was stable and he could pack up the emergency lamps, then head home for the day.

He had help, which made the work go by so much more quickly. Not only because there were more hands and paws and claws to carry everything back to the storage station, but because conversation and company made the work less tedious and boring. He even ran into one of his former classmates, and stayed a few extra minutes to chat with them.

At the end of the day, after everything was taken down, he stopped by Snowin's local bar (the only bar) and got some dinner to go; something for himself, and probably Gaster, if the doctor hadn't yet eaten. Judging by how busy and exasperated Gaster had sounded over the phone, he probably hadn't had the chance.

Sans skipped over to a random hallway somewhere in the core, and began to ask around wondering if anyone had seen Gaster, or if he had gone home for the day. A large fluffy monster helpfully directed him to an unused office two floors down from where he arrived, where Gaster had last been spotted, over an hour ago.

The door to the office was partially open, and Sans peeked inside to find Gaster sitting still as a statue at the lone desk in the room, with his back turned to the door. The skeleton grinned and gave the door a few gentle raps with his knuckle, startling the doctor awake.

"Hm? Who-what time is it?" Gaster asked, whipping his head around the room. His eyes settled on Sans and he blinked slowly, clearing the sleep away and struggling to focus his vision. "Sans?" he asked, "What are you doing here? Taking a break?"

"I was about to head home," he replied, stepping fully into the office and closing the door behind him, "Got a call from Alphys a little bit ago, said everything was stable and I could pack up. You ready to go home for the day? You look like you need some rest."

"Hmmmno, I'm quite fine," Gaster assured him, stifling a yawn, "I must have fallen asleep a while ago, if the others are already gone."

"I think so, didn't see any of them around when I was walking through. So, you wanna go? I brought some dinner." He held up the paper bag with their food, and Gaster's stomach growled loudly.

"Maybe I snould eat," the doctor admitted, blushing, "But I can't leave. I need to figure out what caused this power outage, so it can be fixed. If I can do that tonight, we can try firing the canon again tomorrow."

"Wait, tomorrow? I don't think people are ready for that, Doc. Especially if something goes wrong and we end up with another blackout."

This was the wrong thing to say, Gaster was glaring daggers at him, fingers drumming angrily against the surface of the desk.

"If I fix the problem, there won't be another blackout. And what do you mean people aren't ready? Aren't ready to be free of this hellish cavern?"

 _Aren't ready to be let down again_ , Sans thought. He shrugged. "I dunno, maybe? I mean, who knows if the surface is going to be any better for us than this place is?"

Gaster sighed, bringing one hand up to rub deep circles into his temple. "This is our job, Sans," he stated plainly.

"I know. I just uh... I don't know where I was going with this. Look, our job can wait a few more hours while you eat and get some proper sleep. In the morning, I'll come back here with you and do whatever you need me to, so we can get this figured out. Today's been kind of a bust, sooo..."

"It has, but tomorrow-"

"Look, Gaster? You're not gonna eat these fries _here_. You're not getting any of this warm, delicious, nourishing food unless it's within the comfort of your own home. Trust me, fries like these aren't gonna be as tasty in the morning, if there are any left. But, the cannon's not going anywhere, and _it's_ not decreasing in quality with every passing moment. Come on, what are you waiting for?

Gaster slumped in his chair, sullen and defeated. His drowsiness was beginning to show in his eyes. "Ugh, fine. Let's go."

Sans grinned wide and helped him up from the chair, and they walked long enough to pass by someone to let them know Gaster was leaving for the night. Then, they slipped into the void and back to Gaster's house to eat and rest.

The next day, Gaster had them both up way too early, and they headed down to the core right away, still drowsy and dragging their feet.

"We're going through everything, systematically, from top to bottom, until we find out what went wrong."

"We're gonna need some coffee, then. Lots of it."


	42. Let's make like a tree and exit hastily!

**Notes for the Chapter:**

> Buh buh buh  
> I'll link the playlist at the beginning of the next chapter.  
> buh buh buh
> 
>  
> 
> Also, alcohol mention in this chapter.

Sans and Gaster spent the rest of their weekend tediously searching every corner of the core for some explanation as to what went wrong. They found nothing. Everything on the core's end had lined up the way they needed it to, all equipment was functioning properly, there was nothing should have gone wrong.

So by the end of Sunday evening, every worker at the core was clearly avoiding the frustrated Dr. Gaster, and Sans heard more than one person whispering "Whatever you do, don't bother him." Clearly they had good intentions, giving the doctor space to cool off as he paced the halls of the core. That, or they were worried for their own asses should he decide to lash out. It took some time, but Sans eventually convinced him to leave the facility, dragging him to the barrier so they could check up on the oscilloscope there.

"Shit, I think it's busted," Sans muttered, looking over the machine, "Look, there's a burn-mark here! Gaster?"

The doctor was staring at the barrier, watching it pulse in the dim sunlight filtering through. It had long since healed from their efforts to break it, and had the oscilloscope been functional, it would probably be putting out the same frequency readings it had before. The cannon sat off to the side where they had left it, unhooked from the power source, but still intact.

The scene was the same as it had been before, except for the knowledge of their own failure.

"I'll have Alphys look at it later this week," Gaster mumbled, "Or you can take a look at it if you're feeling ambitious."

Sans stepped up to his side and reached around his waist, pulling him close. "What's on your mind?" he asked, softly.

Gaster's expression remained unchanged, still focused on the barrier. "I can't believe I actually thought this would work."

"I can," Sans replied, squeezing him a bit tighter, "I mean, everything about it makes sense, the plan was **sound** ," he leaned into Gaster a bit, winking, and watched the doctor's stern expression crack a little, "Maybe we rushed things and made a mistake somewhere, maybe that little mutt sabotaged us, or maybe it was a fluke. Let's face it, magic isn't always so predictable."

The doctor hummed affirmatively. "Perhaps I just let the success of the core trick me into thinking anything I put into motion would work out as well."

"Well, that's not re-"

"I'm tired of talking about this. I'm going home. You're free to join me."

"Sure," Sans replied, looking down at the ground, "Let me stop by my place real quick, to grab a couple of books, and some clothes for tomorrow, and I'll meet you there."

* * *

  
"Good morning, everyone! I hope you had a pleasant weekend!" Gaster addressed them the next morning.

From the looks on everyone's faces, Sans gathered no one really had a _great_ weekend, though anything had to beat being stuck at the core.

"I have decided," he continued, "That due to the dangers of damaging the underground's power systems with repeated strain, we will wait at least two weeks before we make another attempt at firing the cannon."

"Wait, when did you decide this?" Sans cut in.

Gaster gave him a sharp look. "It is something I have been _considering_ over the course of the weekend," he replied. "I also want to apologize for rushing everyone. Though we still don't know exactly what caused the cannon's failure, we-"

"Oh, so you didn't actually figure anything out?" Larkeet asked, cutting him off. "You and Sans were at the core the whole weekend, and you couldn't find _any_ leads as to what went wrong?"

"Wait, were we supposed to be working this weekend?" asked Juneborg, "I got told it was alright to go home Friday night, I didn't know we'd need to come back on Saturday..."

"I actually just volunteered to help him out," Sans said with a shrug.

Wickett rolled his eyes. "Of course you did."

"Everyone, please? Listen?" Gaster asked loudly. "If you would."

The room was silent as they waited for him to continue.

"We couldn't find any reason to believe that the core was malfunctioning, or that anything went wrong on that end, no. But something _did_ go wrong, and I'd like to know what that was, before we make another attempt. If it takes longer that two weeks, fine. In the meantime, I'd like to go over everything we did in search of error. We'll regroup, take time to repair any equipment that's been damaged, and maybe do a little bit of organizing. It um... Larkeet, when was the last time we did a spring cleaning, in the lab?"

"Oh, hell if I know," she muttered, "That was Poma's job to keep track of, not mine."

"Right, okay, and he started working with us three years ago, so... well, it's been at least three years since we've done a spring cleaning, then! We'll put that on our list of things to do."

"So, this is downtime? We're not actually doing anything," said Juneborg.

"Well, yes, yes it is. I don't want to rush you all just to fail again," Gaster admitted. "This... didn't go well, and I apologize. But we're going to take the time to get it right, when we try again. Our freedom is worth that, don't you think?"

"Where do you want us to start?" asked Wickett.

* * *

  
Gaster had them start by gathering and organizing all available data they had from the week before.  
Sans had spent the first couple of hours looking over the broken scope and checking what readouts he was able to get from it on Friday before it fried. The huge spike of activity as the cannon fired was apparent, but right before that, nothing unusual showed up in the data. He sighed and leaned back in his chair. He had no idea how to fix the scope itself, and would have to wait for Alphys's help.

He glanced around the office. Juneborg and Professor Wickett were seated at their desks, compiling data from the human souls. Dr. Gaster and Dr. Larkeet were down in the lab proper. Last he heard, they were still arguing about something.

Sans leaned forward to rest his head on his hands, stuck at a standstill. _I could probably start cleaning,_ he thought, closing his eyes. _But that means going down to talk to Larkeet, and interrupting their whole-_

His thoughts were interrupted when he felt something brush against his shin. He yelped, and pushed his chair back away from the desk so fast he almost fell over with it as it clattered to the ground.

Juneborg and Wickett both startled loudly.

"What the hell was that for?!" Wickett demanded.

Sans's fear turned quickly to anger as he spotted the familiar tufts of white fur under his desk. The dog leaped forward as he stepped back again, sporting a tennis ball in its mouth.

"You..." he growled.

"Oh my gosh! Is that that dog?!" June asked, quickly rising from her own chair.

The dog yipped and bounced away, wagging its tail, and Sans pursued. When it leaped from the top of the stairway to the void, he followed.

He lost sight of the mutt in the darkness, but could still hear it barking as he chased after it, following it through the twists and turns of doorways in the dark. "You're not gonna get away this time!" He called out to it. When he was finally right behind it, he dove forward, grabbing it and rolling out of the void and across the floor of the lobby of the lab.

"Whew," he panted, catching his breath as he sat up, "I wasn't built for this kind of athleticism."

"Sans, is that you?" he heard Larkeet call from the office above.

"Thank goodness," Gaster's voice followed, "I was starting to get worried."

"I'm here!" he called back to them, struggling to hold the squirming and wagging dog still in his lap. "What's going on?" he asked, as his coworkers came down the stairs toward him.

"You've been gone for three damn hours, is what, you slacker!" Wickett grumbled.

That didn't sound right. "I was gone for a minute, tops," Sans countered, "I was chasing after this little shit the whole time. No way I'd be able to keep that up for a full hour, let alone three." He glared down at the dog in his arms. How it managed to almost outrun him and keep the tennis ball securely in its jaws, he didn't know. "Don't look at me like that," he growled. It stared happily back up at him, tail still wagging. "Hey, Doc, have we looked into the possibility that this lil guy's to blame for what happened?"

"About that..."

"It was Gaster's fault," Larkeet said plainly.

"What?" Sans asked. His grip on the dog almost loosened enough for it to squirm away, "What do you mean?"

"Here, give me that," said Wickett, reaching for the dog. Sans handed it over, and Juneborg offered a hand to help him to his feet.

"So, when things first went pear-shaped, Gaster wanted to blame it on me, right? But I triple checked EVERYTHING I did, and June here double checked it all, after. _Everything_ was set to specifications, and had the cannon been running to those specifications like we planned, things probably wouldn't have turned out the way they did."

"But Gaster had the cannon set to run at maximum output," said June, "which turned out to be quite a bit higher than what we planned for. It might've had something to do with the parts we had to switch out."

Gaster was looking away, a dark blush of embarassment spread across his face. He said nothing.

"To be fair," Larkeet continued, pulling her cellphone out of her coat pocket, "it was really just a miscommunication. It could have happened to- what?" She interrupted herself, glaring down at her cellphone screen in confusion.

"What is it?" June asked.

"Oh uh, nothing," She said, looking back up at them, "I'll... be back in a few minutes." With that, she turned on her heel and marched quickly toward the elevator.

"So when did you guys figure this out?" Sans asked.

"In the three hours you were gone." said Wickett, flatly.

"Right." Sans turned his attention to the dog, now in Wickett's arms. "Guess I owe you a game of fetch then, huh?" he asked, reaching out.

"You what?" Gaster asked, finally speaking back up.

"I saw him on Friday, promised him a game of fetch if he didn't cause us any trouble. Maybe he really didn't."

The dog yipped excitedly, dropping the slimy tennis ball into his palm. He grimaced, but pulled his arm back nonetheless, and flung the ball as far as he could, toward the back entrance of the lab. The dog quickly wiggled out of Wickett's grasp and went bolting forward, catching the ball in its mouth, seconds before it slid through the door.

"That's so surreal," Juneborg whispered, watching the space where the dog had disappeared. Wickett was distracted with wiping the dog's residue from his labcoat.

Sans watched Gaster make to turn away, but grabbed for the sleeve of his labcoat, stopping him. "Hey, Doc, don't beat yourself up about this, okay?"

"On the contrary," Gaster said, turning back to face him, "at least now we _know_ what went wrong. And because it was my fault, it's something I have control over next time. I just... wish it hadn't happened at all." He did his best impression of a carefree shrug. Sans chuckled.

"Well, what do we do for the rest of-"

"AlrigHT, EVERYONE, THERE'S BEEN A CHANGE OF PLANS!" Larkeet bellowed as the elevator doors slid back open. "WE ARE GETTING THE HELL OUT OF HERE."

"Is something wrong?!" Gaster asked.

"Not really," she chirped, "It's just _so_ damn boring here, with nothing to do. How about we take the rest of the day offfffff, aaaaaand go get a few drinks?"

"Wh- You can't be serious," said Wickett.

"Oh, I am," she insisted.

"It's the beginning of the week,"

"And you know who didn't get any time off this weekend to recuperate after all this heck went down with the cannon?!" she asked, gesturing with both arms to Gaster and waving them madly. "How can any of us expect to do a good job here if our _boss_ is flagging from overexertion?! We worked hard last week, and though we weren't successful, we still deserve a little break! I say we grab a few drinks together as a team, and boogie down!"

Her suggestion was met with silent, confused stares.

"Juneborg! Help me out! You're young! You're... hip? I'll bet you know somewhere cool we can go and get our social on! Right?"

"Oh, um... sure? I mean, my uncle Iceborg actually owns a bar in the capitol. It's a pretty cool place, I guess. It has a dance floor, and everything."

"PERFECT!" Larkeet shouted, flapping her arms excitedly, "Let's all get the hell out of here then!"

 


	43. Quantum Loop

**Summary for the Chapter:**

> Might be a bit messy till the morning. I'll make some edits after I get off work.

**Notes for the Chapter:**

> Please be aware there's some heavy alcohol usage in this chapter.
> 
>  
> 
> Also, wooooooooo! The playlist that inspired/is inspired by this fic is now uppppp!  
> https://8tracks.com/pomander/something-you-can-t-measure
> 
> Aaaand please to be looking at the comic someone made, it beautifully sums up this entire story!  
> http://imgur.com/a/9cd2H

"Man, I can't believe they turned this place into something so nice! How long has your uncle owned it, June?"

"Oh, ummmm, about five years, I think?" she said, rubbing one finger around the rim of her glass, "Maybe six. Why, what was it like before?"

"An absolute _dive_." Wickett took a long drag of his cigarettte. "Used to be called 'Rudy's' or some shit."

"it was known for being _not the greatest_ , but this? This is downright classy!" said Larkeet as she looked around them. "We used to come here at the end of the week, if we needed cheering up. Work on the core was a bit uh... shaky? In the beginning?"

"It was," mumbled Gaster. He toyed with his straw, his eyes wandering the club around them, noting things that were different, things the new owner had decided to keep the same. His gaze settled on Sans next to him, before returning to the rest of his team. "The core is functional now, so it would be easy to look back at it as a total success. But there were several roadblocks we had to overcome, especially in the beginning."

"Like finding a way to sink the base of the core into the magma, but keeping it insulated from the heat so people could actually work in there long enough to get it set up!" Larkeet offered.

"Yes, like that," Gaster agreed.

"That sounds like it was a challenge," said June, "I wish I could have been on your team back then, been one of the ones to help figure everything out."

"Yeah, me too," said Sans. Gaster felt one of the skeleton's hands stroke the outside of his leg briefly, giving it a gentle squeeze before it was stealthily returned to the table.

He smiled to himself, checking to make sure none of his coworkers had noticed.

"You two would have been stressed to hell and back for no reason," Wickett assured them. "Besides, finishing this blast cannon and getting the hell out of here is a much bigger accomplishment."

"If we ever succeed," Gaster added.

"Aaaaaalright, looks like we're ready for another round of drinks!" said Larkeet. She hopped up from her seat at the table and made her way to the bar.

"Like you said," Sans offered, "a few roadblocks, shaky in the beginning, et cetera. But we'll get there."

"I hope so," said Gaster, quietly.

"And I hope you're ready for another drink!" Larkeet chirped, returning with a tray of beverages. "Tonight's our night to unwind, so let's cut the sad talk!"

They spent the next hour chatting, taking turns buying rounds at the bar. Wickett brought over a group of steaming hot-shots of some foul-smelling liquor, And everything Larkeet brought back for them reeked of cinnamon. Gaster started to recall why he never invited his team drinking anymore.

As the haze set in, he excused himself to the washroom, rinsing his face in the sink to clear his head a little. When he returned to the table, they were short two people; two short people.

"Where did Sans and Larkeet go?" he asked, sitting down slowly.

Wickett shot a thumb over his shoulder toward the dancefloor behind them. "Bird lady begged him for a dance, so now they're off cuttin' a rug."

Gaster glanced over the dance floor, which, while not overly-crowded, was populated enough that finding the two was tricky. He finally spotted them, swaying and bobbing to the heavy, upbeat music. Larkeet had one arm over San's shoulder, and was leading him from side to side, swinging her hips and stomping her feet rhythmically. Sans was busy looking from her feet to his own, clearly having trouble keeping up. Whether it was inexperience on Sans's part, or drunken hubris on Larkeet's part, Gaster didn't know, but sight of them bumbling about made him smile.

"I think I'm going to go join them," said June. Wickett scooted out of her way, and she shimmied her way over to the other two. She leaned down to tell Sans something Gaster couldn't hear over the music, and the skeleton turned his attention to Gaster, waving him over.

Gaster laughed and shook his head. _I haven't had enough drink to be out there_ , he signed. Sans cocked his head to the side, shrugging and beckoning the doctor again. Gaster realized his mistake; Sans had no idea what he was trying to say. Sighing, he held up his half-empty drink and pointed to the glass with a grin. At this Sans shrugged and waved him away, returning his attention to Larkeet and Juneborg, trying to keep up with them.

"You gettin' the next round after that one, then?" Wickett asked him, nodding to his glass.

"I might," said Gaster. He took a long sip of his drink and winced, the cinnamon absolutely overpowering. "No, I definitely am, what do you want?"

Five minutes later, their three coworkers joined them at the table again, pleased to find full glasses waiting for them.

"Hey, thanks Gaster!" Larkeet said as she slid back to her seat.

"It's Icewater," he told her, "you can thank me in the morning when you don't have a hangover."  
  
"Oh man, I'll thank you now! It's fuckin' warm in here!"

Gaster felt a tapping on his shoulder, and looked over to find Sans, sweating, breathless, and beaming at his side. "Hey, Doc, wanna dance for a little bit after this?" he asked. His face was flushed, though whether from the heat or the alcohol, Gaster wasn't sure. Perhaps it was both.

"I um, I really should finish my drink first-"

"Oh, don't even!" Larkeet cut him off, "Liquid courage is one thing, but if you have too much more booze, you're not gonna be able to stand up straight, and then where will we be?"

"On the floor?" Wickett asked, lighting up another cigarette. The others laughed.

"Please?" Sans asked, leaning in a little closer "I wanna see if you live up to your name."

Gaster felt his face heating up. "M-my name?" he asked, quietly.

"Yeah, _Wonderful Dancer_." Sans's grin widened and he pulled the doctor up to his feet.

"Oh, that's not really my- Woah!" Gaster let himself be dragged toward the dancefloor, the alcohol definitely toying with his coordination.

"Hey," Juneborg called after them, "You want me to come out there with you? You've had a lot to drink!"

"I'll be fine!" Sans shouted back to her as he turned toward his partner. "I hope so, anyway," he added, his voice lower, "Your assistant tells me you're a trained dancer. I hope I can keep up." He winked at Gaster again, clearly more affected by the alcohol than the doctor himself.

Gaster snorted, bringing hs hand up to his face to cover half of it. Of course she would say something like that "Did she tell you I've only been trained in classical dancing, for Asgore's formal parties, and that I'm terribly out of practice?"

"So what you're telling me right now is that you were trained specifically to handle Asgore's balls? Cuz, I think she might've left that part out."

Sans doubled over in laughter. Gaster, face full flush, turned his attention back to their table to find Larkeet much in the same state.

"I'll be right back," he decided out loud, "I'm going to request a different song."

* * *

 

Sans had fallen to the floor laughing, and was still wiping tears from the corner of his eye when the song faded from a heavy, electronic thumping, to something slightly more accoustic and jaunty. He looked up to find Gaster approaching him, and got up to his feet just in time to take the doctor's hand.

"Alright, Sans," said Gaster, grabbing Sans's other hand and placing it forcefully on his own hip, "I'll try and remember how this is done. Please follow my lead, and we should do just fine."

"Whatever you say, Doc," said Sans with a grin. He gave Gaster's hip a little squeeze, and got a squeeze on his shoulder in return.

"Step back then," Gaster instructed him, moving in closer, "And on the count of three..."

Sans was just a little too drunk for what happened next. Dr. Larkeet had assured him that Gaster would be clumsy, tripping over his own feet if he tried to dance with even the slightest bit of alcohol in his system. "It'll be hilarious," she had assured him. Sans wasn't laughing. He was _having fun_ , but he wasn't laughing. Gaster was clearly out of practice, but he was _into it_ , leading their dance with his whole body in addition to verbal instructions. He was making it easy for Sans to keep up. And though one or both of them would occasionally trip or stumble, or step on the other's foot, Gaster would laugh it off and resume confidently.

Gaster spun him by the hand and pulled him in closer, meeting his eyes with a warm smile that made Sans want to melt. He was beginning to sweat again, his face heating up from the feeling of Gaster's body moving so closely against his own, only thin layers of fabric separating them as they moved around the floor.

Their song faded out to something with a slower tempo, and Sans was suddenly very aware of his coworkers watching them. "Hey, do you think we should, um," he paused, the haze of alcohol still hanging over him, making it harder to find the words he needed, "Should we be dancing like this? This close? I mean, everyone can see us."

"If no one said anything about Larkeet's feathery mitts all over you, they shouldn't care about mine," Gaster said plainly, giving Sans's shoulder another squeeze.

Sans chuckled, leaning into Gaster further. At that point, he didn't really care what his coworkers said. Gaster was comfortable and warm and smelled divine. He let himself get lost in the feeling of being close, only brought out when he heard Gaster's voice.

"You do know that 'Wonderful Dancer' isn't my real name, right?" the doctor asked him.

"Could've fooled me, with that little display," Sans said, grinning widely again.

Gaster pulled him closer. He lowered his voice, leaning down slightly so Sans could still hear him. "Would you like to know what my name is?"

Sans pulled back just far enough to look the doctor in the eye. "You said you never use it."

"Correct."

"Then I don't need it," he said with a shrug.

Gaster beamed at him, "I suppose not," he said lowly, leaning in closer.

Their foreheads were practically touching when Larkeet stormed up to them, with Wickett and Juneborg in tow. "Alright, fellas! Break it up!" she bellowed "The dance floor's for everyone!"

They pulled apart quickly, faces flushed, as the music changed again, and their coworkers crowded in to join them.

Gaster's inexperience with every other form of dance was apparent as he bobbed stiffly to music he didn't recognize, watching everyone else for cues on what to do. Sans took this opportunity to have a little fun with him, grinding against him and watching him flounder. After about a minute of that, June pulled him away from the doctor, and plopped him in between her and Larkeet again.  
  
Wickett left them after one song to return to the table, clearly uncomfortable with being made to dance at all. Gaster followed him dejectedly, leaving Sans, Larkeet, and Juneborg on the floor again. Every time Sans looked up, he caught June turning away. She kept looking over at him, though, every time he turned his head he could sense it. He eventually ducked out, leaving just her and Larkeet, as he made his way over to a nearby moldbygg.

He wiggled his hips at his new dance partner, and laughed when it began jiggling wildly back at him. He tried and failed to imitate it's movements, and ended up slumping with his back pressed to it, half-heartedly shaking his shoulders as he tried to regain his balance.

Their dance was cut short when Gaster approached them. "Pardon me," he said, addressing the jiggling monster, "but he's spoken for. May I?"

The Moldybygg swayed from side to side as it wiggled away. Gaster grabbed Sans's hand to steady him, and laced their fingers togther.

"Alright, that's enough flirting with strangers," he said sternly, leaning in, "What do you say we call it a night?"

Sans blinked hard, looking back over to the monster he was just dancing with. "Was I, really?" he asked, "Shit, Gaster, I didn't even-"

Gaster reached up to stroke his cheek. "It's fine, you didn't know, it's fine. I just think we've had our fun. You're very drunk, and I'm worn out, and Juneborg keeps shooting me dirty looks. What say we skip out and head back to my place, hm?"

"That sounds fantastic." Sans's head felt fuzzier than a cottonball, and he wanted to sit down. "Shortcut?" he asked.

"Yes, allow me," Gaster offered, taking him to the edge of the room. He opened a portal to the void inside the doorway to the washroom, and led them through.

"Fuck," whispered Sans, "nothing sobers you up like a journey through absolute darkness."

"I'm sure you're still actually drunk," Gaster replied, jostling his shoulder.

Sans made an exaggerated lean to the side, "Yeah, I bet you are, too," he said, grabbing for the doctor's hand.

"Oh, I am, no doubt about that." He squeezed his own hand around Sans's. "I could stand to drink more, but as it is, I am drunk." He stuck out his arm and spun Sans around, dancing with him playfully in the dark.

It was then that Sans stumbled, falling to the side for real, and dragging Gaster down with him. The doctor panicked and reached forward, opening a gap as they fell, and sending them lurching out of the void and onto the cold hard floor of the lower lab.

"Wow, that smarts," said Sans, turning over and rubbing his knee. "You okay, Doc?"

Gaster muttered a soft "fuck," his face pressed to the floor. "I'm okay, I'm okay," he said, as Sans reached to help him up. "That was unpleasant," he added.

"A little, yeah," Sans agreed. "But hey, we made it to the lab! Score one for us.

"I was aiming for my house," the doctor grumbled, sitting up fully. "Oh, I should message Larkeet and let her know we're gone for the night, so she doesn't come looking for us."

"Good idea. After that, maybe we can wait a bit before we go back to where we can't see our own feet?"

"Hm. Good idea."

They found themselves in front of the lower lab's vending machine, and so the only sensible thing to do was to have a soda while they got their bearings. Before either of them had finished their drink, they heard the elevator land, and Larkeet came pouring out.

"Alright, you got me down here, _ha ha_ you guys," she said flatly, staring them down.

"Wha?" asked Sans, wobbling.

"Larkeet, how did you get back here so quickly?" Gaster asked, his gaze flicking from her to a puzzled Sans. "Wait, how long were we gone? Is everything alright?"

"What do you mean, gone? You were upstairs talking when I took the elevator, and now you're here? And you- oh god, you **reek** of booze! What the hell, have you been drinking?"

"Wait, what?" asked Sans, eloquently.

"I don't know, that's what I'm telling you! It's the middle of the afternoon, and you two are down here, drunk?"

"The... are you joking?" whispered Gaster.

"Doc. Doc, holy shit." Sans could feel a grin spreading across his face. "It's just like with earlier, with the dog?"

"Did we-"

"Jeez, that's like, five hours? We did the thing!" He shot forward, wrapping his arms around Gaster, who had gone completely stiff.

"We did," he muttered softly.

"You two owe me a damn-good explanation," said Larkeet flatly, staring them down.


	44. You fell, alright.

**Notes for the Chapter:**

> it's been almost three weeks. What a nightmare. If any of you don't know, I drenched my laptop. Fucked it up real good. I lost this chapter and had to start over, either on my phone, or on my backup laptop, which freezes randomly. Didn't wanna, that's why this is so late. My apologies.  
> But things are better, now! New computer, much speed.  
> I hope you all have been well!

"The thing about wanting an ice cream-" Gaster slurred, his intoxicated brain struggling for the right words, "No wait, I mean the thing about wanting an **explanation** just like that- It's like asking for an ice cream cone. I mean, I don't hav- have one on me at the moment? But I would be happy to find one for you, if you give me time."

"And you couldn't say, fetch me one right now, with that new teleporting thing you do? That _is_ new, right? Or have I spent the last several years missing something really obvious?"

"No, no! It's- It's new," he assured her. He saw Sans wobble next to him, and placed a hand on the skeleton's back to steady him. "we, Sans and I, we are still learning things about it. About the void space. Where we teleport, and which is now connected to- possibly- to time travel." His mind reeled at that. _How?_ "I don't know at the moment, really."

Larkeet did not look impressed, that eyeroll was not the mark of a person who understood and accepted what he was saying.

"But that's not even important," Sans drawled, "I mean it is, but not right now. Dr. Larkeet, if this is still the early afternoon, you have to get us out of the lab. Like, the fate of the world depends on you convincing the entire crew to get absolutely sloshed." He giggled, at risk of tipping over again, but Gaster held him firm. "Isn't that just the best mission ever? I mean, if you don't, it might cause a paradox. And if you've seen the movies I've seen, if you've read the books? That's bad."

"You guys _are_ pulling my leg here, right?"

"I promise we aren't, Larkeet," said Gaster, "Look, I know this all seems like a big joke, but we are not in the state to explain ourselves right now. The best I could do is give you a proper explanation for all this, sayyyyy, tomorrow morning? In the meantime, if you don't take us, the us in the lobby, out of the lab immediately and convince us to drink? Then we won't get drunk, we won't have time-traveled, and we won't be having this converation." He cringed as he spoke. "That's a bit too much for me to process right now."

"Yeah, I get it, you're drunk," she sighed. "And don't get me wrong, I'd love an excuse to get out of work. I'd take any excuse to get out of work. But I expect an explanation in the morning, so be ready for that!" She turned on her heel, marched back to the elevator, and Sans and Gaster were left alone again.

"What now?" asked Sans, "Like, do we really hafta figure this out right now?"

"Oh absolutely not," Gaster assured him, "We're in no state to be analyzing how we- we just sort of drunkenly stumbled back several hours. I don't even know if I'll remember this conversation in the morning. What I think we should do is get some food now, and wait for the effects of the alcohol to wear off, so we can actually think. What say you?"

"Yeah, no, that sounds great. I am. Definitely hungry."

"Let's go somewhere then, anywhere you want."

* * *

 

Sans kind of forgot that taking a shortcut through the void wasn't a good idea while they were still drunk, but any concerns he might have had melted away as Gaster followed him into the warmth of Grillby's. The whole place smelled like booze and burgers, and just felt so much like home. There were few patrons at that time, so the two of them strolled right up to the bar and sat down near the center, as the owner, (Grillby, who would've guessed?) approached them.

"A bit early to be in the state you're in, no?" He asked them quietly.

Sans and Gaster chuckled, shooting a quick glance to each other.

"Well, maybe," said Sans, "but we're not here to drink. I'm curious about something I saw on your menu the last time I was here. The Greaseburger? Sounds divine." He slumped his head down until his forehead met the surface of the bar, surprisingly cool wood that felt nice against his skull.

"It's something I can make for you, if that's what you're wondering," said Grillby, "And you, sir?" he asked, addressing Gaster.

"Mozarella sticks, and some water?"

"No water, sorry, but I've got some seltzer if you're feeling queasy."

"That would be fine, thank you."

Their food arrived shortly after, steaming plates of greasy, salty, cheezy goodness. Sans immediately shoved a french fry into his mouth and moaned at how hot and salty it was against his tongue. He heard the bar's owner chuckle and felt Gaster's hand on his back again.

"So, what brings the two of you out to Snowdin?" Grillby asked them.

"Ah well, we've been out drinking all ni- erm, all _day_ , and need a chance to rest and clear our heads."

"Totally worth the trip to come here," Sans adds, placing a hand over his mouth to be polite. That should cancel out talking with his mouth full in the first place, right?

"I'm glad you think so," Grillby replies with a grin, "Let me know if you need anything else."

It turns out they didn't not for a while. Within the span of an hour, they had finished their food and Sans already felt so much better, his head clear and his body not quite so heavy. He was still a bit dizzy, though.

"Okay, so. We're feeling better, maybe we should, brainstorm this little situation, yeah?" he said, tapping his fingers on the bar.

"Mm, we should. Do you have a pen?" Gaster asked him, grabbing a nearby napkin.

"I think so... " Sans felt his pockets. "Maybe?"

"I've got one," said Grillby. He walked over to them from down the bar and reached under the counter, pulling out a pen and offering it to Gaster.

"Oh, thank you so much! Now, Sans. What do you remember from earlier, before we ended up at the lab?"

"Um," Sans folded his arms in front of him on the bar as he thought, earlier was still a cloudy concept. "We were on the dance floor, right? And you said head home. Your home. So we left and entered the void. And we were dancing around, and I fell. You tried to catch me, I think. And when I opened my eyes, we were on the floor in the lab."

"I caught you," Gaster assured him, "though I didn't do much to break your fall. Nor you mine." Sans looked over and watched him stop writing, to rub the side of his head with his fingers. "Why did I try and exit the void when we fell? It's not like it would have done any harm, to have fallen and landed in there, would it?"

He shrugged. "I don't think so, I mean you just panicked or something, I guess. I mean it didn't really hurt me when I skidded to my knees when I... oh shit."

"What?"

"Okay, earlier today, when you guys said I was gone for hours, I wasn't. I was in the void the whole time, and it was maybe a minute or two, I swear."

Gaster put the pen down. "I believe you," he said, looking Sans in the eye.

"So, when I jumped to catch the dog, and skidded into the lab, for three hours to have gone by, without my knowledge? That's a little weird."

"And then we fell together and ended up jumping back several hours. Could it be falling through the void that causes it, then?"

"Maybe it's where you fall, or how fast you're falling," Grillby muttered from down the bar, not looking up from the glass he was cleaning.

Sans and Gaster stared down at him, surprised he had even been listening.

"Of course, I have no context for what you're talking about," he added, his flames turning a redder shade, "it just seemed that was the direction your conversation was headed. Please excuse me."

Sans watched him head back into the kitchen, while Gaster scribbled something down on the napkin.

"No, I think he has a point, though," the doctor mumbled. "About velocity, I mean. When we take a shortcut, we walk through, correct,? And there isn't any noticeable change in time. But jumping or falling through-"

"Or being dragged," Sans added, his thoughts jumping back to the day he had been pulled through the void as a child, and ended up home before the schoolbell had even rung. "Maybe where we are does matter, though. It isn't something I'd rule out."

"We never know where we are in the void, though. It's not like we have a map of the place."

"We could _make_ one."

"I... I like the way you think, you know that?"

Sans grinned broadly. "Really? I thought you just hang out with me 'cause I'm cute."

"No, I'm sure I'd still be drawn to your intellect, even if you weren't cute. But it helps." The doctor winked at him. "So, what I'll tell Larkeet in the morning is..." He flipped the napkin over and began to write again. "We accidentally found a secret void that seems to allow access to different points in space and time. We accidentally fell back several hours and created some sort of time loop, and are possibly doomed to make several more in our efforts to fully understand our accidental discovery."

He underlined those last four words repeatedly, then turned to Sans. "How does that sound?" he asked.

"Don't forget to tell her that this was all an accident," Sans replied, "she needs to know that."

Gaster laughed, folding the napkin and slipping it into his pants pocket. "So, since that's out of the way, and we have a little extra time this evening..." he began, propping his elbows up on the bar and resting his chin in his hands, "How would you feel about celebrating a little? Maybe having a few more drinks before heading home? The night is still young, after all."

"I think I could handle that." Sans smiled and leaned towards him.

Sans wasn't sure how many drinks they had had after that, but it certainly wasn't just one or two, and he wasn't handling it very well. Neither was Gaster, if the way he giggled and leaned into Sans was any indication.

"Alright, alright, I think- think it's time to go. Back home," the doctor managed to get out, resting most of his weight onto the bar.

"Yeah, it's getting late," mumbled Sans, "You want me to um, should I open up the void and we can time travel again?"

Gaster shook his head, reeling, "No, let's walk," he said, firmly. "We aren't going to make another loop back like that. Not tonight. Not again."

They payed for their drinks, Gaster returned the borrowed pen, and they slowly shambled out, mostly due to Gaster struggling to keep upright. Sans kept one hand on the doctor's lower back as they walked. "I've got you," he whispered. Gaster wrapped an arm around him in return as they made their exit into the cold air of Snowdin.

They hadn't made it more than ten feet when Gaster slipped on a patch of ice. He lurched back, pulling Sans with him into a pile of snow.

All Sans felt was the sudden tug, then everything was cold. It took him a moment to put together what happened, and another moment to realize Gaster was lying under him. He panicked.

"Doc, you okay?!" he asked, pulling back to look over Gaster's face, checking him for damage.

The doctor stared back up at him, wide-eyed and blinking. "I'm okay," he said after a moment, "That scared me, but I'm fine."

"Did you hit your head or anything?" Sans got ready to move off to the side so Gaster could get up. He was halted by Gaster reaching up and grabbing onto his shirt, keeping him in place.

"I'm fine," Gaster repeated with a smile, "I just don't feel like moving." He winked and moved his hands to the top of Sans's legs. "Let's just stay here for a moment."

Sans rolled his eyes and nestled back down over Gaster, shielding him from a small wave of snow that the wind had kicked up towards them as it passed. The street was otherwise empty, and he took the opportunity to plant a kiss on the doctor's cheek. "Let me know when you're ready to get back up," he whispered, planting another kiss on the opposite side.

In response, Gaster's arms wrapped around him and he was held tight, keeping them both right where they were.

They probably could have stayed like that for hours, if something hadn't come by to interrupt them. Sans felt the light and sudden smack of a piece of paper flying into his face as he was leaning in for another kiss. He shouted, startled, and Gaster released him immediately, reaching up and pulling the paper off of him.

Gaster held the small paper between them and flipped it over once, twice, and again, smiling up at Sans. "Looks like we were meant to be here," he whispered, smugly, "the fate of the world depended on it."

It was then that Sans noticed the color of the paper Gaster held up to him, the writing on one side. ' _Don't be afraid to ask for help_ ,' it said.

Sans took the paper and slipped it carefully into his pocket as he sat up and checked the street around them one more time. They were indeed still alone, and the paper could have come from anywhere. His head was spinning, and the only thing that grounded him was Gaster reaching up and touching his chest gently.

"Are you alright?" the doctor asked, quietly.

"Never better," Sans answered with a small smile. "You know you're gonna have to go back and do that, once we figure out how, right? Another complete loop."

"It's going to be difficult, not giving myself away," Gaster told him, "I'm sure even Past You will be able to tell I'm absolutely smitten." His hand moved to the side of Sans's face, stroking it slowly.

Sans felt that familiar warmth creeping in at the touch. "Never would have guessed," he said lowly.

He got up and helped Gaster to his feet. They brushed the snow off of each other's clothes, with the occasional lingering touch.

The next morning, Sans wouldn't remember how they eventually got back to Gaster's house, just that they had gotten back safely. He wouldn't remember Larkeet calling Gaster to check up on them, once she figured out they had left the club to complete their time loop.

He wouldn't remember what Gaster whispered to him once they were lying next to each other in bed, curled up warm under the blankets. Not the words, anyway. He would only remember the way it made him feel.

**Notes for the Chapter:**

> [ The song that inspired most of this chapter, tbh](https://www.youtube.com/watch?v=6XXfqPRG4TQ)


	45. Rattled

"G'mornin', Dr. Larkeet. What's up?"

"You guys know you're over an hour late, right?"

"wh-" Sans struggled to keep his eyes open, squinting over at Gaster's bedside clock. "Shit, you're right. I'm sorry, we'll be right there."

He heard laughter on the other end of the line. "He is. I told you guys. June, you owe me a soda. Oh, Sans? Hurry it up. You guys can snuggle later, it's work time."

Sans groaned and let his phone drop to the floor. His head felt like it was full of rocks. He rolled back into his spot on the bed, and Gaster's arms immediately wrapped around his midsection, pulling him closer. Jeez, it felt great. He didn't necessarily want to ever stop being held like that.

"Hey, Doc, we're late for work," he whispered. Gaster's sleeping face was beautiful, even as his brow furrowed and he rolled his head from side to side into the pillow.

"Not going in," the doctor mumbled, "I'm dying."

"Heh, you too, huh?"

He managed to drag the doctor to work anyway, after a quick meal of toast and tea. They arried at the lab to find everyone else just sort of chilling. Wickett was seated near the wall with a book, Juneborg crouched and rifling through a small bag, and Larkeet was leaning against the wall near the coffee station, holding a big steaming mug of (presumably) coffee.

"Oop, they're here! Breaktime's over!" she chirped as they arrived. She set down her mug, stretched her wings, and marched over to them.

Gaster folded his arms. "You woke me up so I could come in, and you're not actually working, either?" he asked, sternly.

"Can't get any work done without our boss here to tell us what to do, eh?" she said, beaming.

"Probably won't get anything done regardless," said Wickett.

"Then what'd we need to come in for?" asked Sans.

Larkeet shrugged. " _We_ had to, didn't we? Fair is fair. We're all just as tired and hungover as you two."

"I'm not," said Juneborg, making her way toward the office stairs.

"Right well, we've got one responsible person on the team, who's probably only half as hungover. Anyways, WE all got up early, so it's still fair. And you promised me an explanation for... " she waved a wing at Gaster, "whatever it was that happened yesterday, and I'm holding you to that."

Gaster slapped a hand to his forehead, then hissed at the unnecessary pain he had just caused himself. "Ugh, that's right," he groaned, "I left the napkin in my pocket."

"The napkin?" Larkeet whispered, turning to Sans.

"My explanation, I wrote everything down last night. Hold on, I'll be right back.

He held up one finger as he walked back toward the Lab entrance.

"How convenient, really," Larkeet groused.

Sans shrugged. "He'll be back in no time, his pants from yesterday are like, smack in the middle of the floor... Er, uh..." He found himself blushing at the knowing look Larkeet gave him. "I mean probably, anyway. Look, I'm gonna go upstairs, and, do stuff. Work." He then marched up the office stairs before she could say anything else on the matter.

Juneborg sat at her desk in the upper office, hunched over in her chair. "Hey, June, what's up?" Sans asked, pulling out his own chair and sitting down.

"Hm? Oh, not much!" she said, cheerily, her eyes locked on the screen in front of her. She turned to Sans. "What's up with _you_ , anything new?"

"Not really. Pretty crazy night though, last night, yeah?"

"Oh, yeah! It was fun." She shifted in her seat, tilted her head to the side. "You uh, you hungover, still?"

"Egh, yeah, just a bit," Sans replied, chuckling nervously.

"Oh, hold on! I've got something for that!" She reached down to her bag on the floor and began sifting through it.

"Really? Thanks," said Sans, leaning back in his chair. He turned to his computer screen for a moment, and turned back just in time to see the AIRHORN in her grasp. He didn't have enough time to move away.

The AIRHORN screamed as she pushed down the button, and the loud, shrill _**HRRRNNKK**_ echoed through the lab.

Flinching had done nothing for him. Sans could feel the sound reverberating through his skull in painful throbs as he closed his eyes and clenched his teeth. His hearing was nothing but ringing sounds for several moments after it stopped. As it came back, he heard a muffled cry of "What the fresh hell was that?" from down in the lobby. It sounded like Gaster. Sort of.

"What. The fuck? Was, that?" Sans groaned, slowly opening his eye sockets.

"Everything okay up there?" Wickett called up to them.

"We're fine." June responded, still staring down at Sans. He definitely didn't believe that.

"What even was that?" he asked her again, "What's your problem?"

" _That_ was payback, for letting me worry about you!" She whispered harshly. "And for basically everything that happened last night."

"What do you mean letting you worry? Is my memory foggy or something?" He thought for a moment over the night's events, but couldn't recall any conflict. "What happened last night?"

She scoffed, a metallic hum catching on her mandibles as footsteps sounded from the stairs.

"Is everything alright, you two?" Gaster asked, cautiously approaching them.

"Yeah, we're cool," Sans replied, sitting up straight. Juneborg said nothing. "Just a prank, all in good fun."

"Right, well then. Juneborg, I was wondering if you could-"

"I'm busy digitizing old documents and storing them in our archival," she interrupted, "Unless you've got something really urgent for me to do, it'll probably take a while."

"I'm gonna help her out today," Sans added, "so maybe it'll take less of a while."

Gaster shifted from foot to foot, looking over the two of them carefully. "Excellent. Well, if either of you need me, I'll be down in my office. Dr. Larkeet will be down in the lab proper, as well."

"Alright, thanks," Sans said, with a smile. He turned back to his computer and opened up the monitoring program for the oscilloscope. Everything was running fine. No problems. He listened Juneborg returned to her desk, and Gaster's footsteps receded down the stairs. "So, June," he began, not actually looking over at her, "what exactly did I do to grind your gears?"

She turned in her chair. "You're dating our boss," she said, plainly, "I found that out last night."

"Oh." Welp, that was indisputable. He sure was. Nothing helping that. But why was she so upset about it? He carefully measured his next words. "You got a problem with that?"

"Several!" June pushed her chair back and stood up quickly, whirling around to face him proper. He turned to face her as well, still in his chair. "Like, do you want me to run down the list?!"

Did he? Was there actually a list?

"Yes," he answered, slowly, "please."

She sighed. "I don't actually have a list. I'm just pissed because _apparently_ everyone else in the lab knew. Except me. You didn't bother to tell me, even though I was worried for you. Even though I TOLD you I was worried. I mean, last night, when we were on the dancefloor and I told you Gaster was staring at you, you just waved him over. Like you didn't care he was being totally creepy."

"He wasn't being creepy."

"In hindsight, maybe not? I mean I guess NOW that I know you're dating, it's a normal thing, but from my standpoint? Yeah, it was creepy as hell. Because from my standpoint, when you told me he wasn't bothering you, and it was nothing to worry about? I started to wonder if maybe you just didn't know how much he stares at you."

Sans felt his face heat up. "H-how much uh, does he stare?"

"Wow. A lot, Sans. Congratulations."

"Sorry."

"But what would you do, Sans, if he _was_ bothering you? If he was staring at you and being flirty and you didn't like it? What if you told him you didn't like it, and he didn't care?"

"I..." was 'run like hell' an option? "I'd take it up with Asgore, I guess."

"His _friend_ , Asgore? Who's side would he take? What if he decided you were the problem, and put you out of a job?"

"You've thought about this a lot, haven't you?"

Her posture stiffened. "It's not a good thing, to be in a position like yours. Trust me."

He laughed, nervously. "Why, have you dated Gaster, too?"

The glare she gave him told him she didn't appreciate his humor. "I got involved with one of my professors, back in college," she admitted, "It was kind of an accident; I thought I was just being friendly. By the time I realized it was a problem, it was too big of a problem to actually handle on my own, you know? I tried to talk with him about it, and he would always say things like, 'Gosh, you're right, it would be so much easier for us both if you weren't in my class!' so I tried to go around him, and take it up with the dean. His friend, the dean, who had known him for years. It didn't go well."

"Oh."

"Yeah. I ended up getting his wife involved in the situation, also by accident, and she's the one who put a stop to it. She's a great lady, we still talk, sometimes."

Sans leaned back in his chair. "Jeez, I mean, that's awful," he muttered, "I'm sorry."

"Not your fault. I guess I was projecting, or something. I just, you know. Didn't want to see the same thing happen to you. Because it's not fun, when you can't refuse someone without screwing yourself over."

"Yeah... Sorry for making you worry. Gaster's not like that, June. I swear."

"You're sure?"

"I'm sure. It's not like I've given it no thought, you know? And even he warned me away from it, at first. It- this whole thing was never supposed to happen." He laughed, dryly. "I just had a crush on the guy, just a silly little crush. Then he found out, and he warned me away from 'flirting with someone who outranks me' and all that hoo-ha, but then I guess he changed his mind about it."

"Why?"

"Probably realized he was being a hypocrite. Heh. I mean he basically did the same thing, flirting with his boss, and it didn't go well for him, either. Guess I got really lucky. It was just supposed to be a fling, I think. And it could have stopped there, I mean there have been a few points where either of us could have walked away, now that I think about it. But neither of us did, and things escalated. Usually in a good way. I mean we both have learned a lot about each other, and I think it's turned into something... well, it's a lot more than a fling, that's for sure."

"Could you still walk away now? If you needed to?"

He shrugged. "Probably, yeah. I don't want to, though. I know Gaster's not perfect. He's- well, yeah, he's definitely a flawed person. But I also know he's not gonna take advantage of his position over me. Like I said, I got lucky. Things are working out well."

"I'm glad," said June, "I'm sorry for getting so upset, it's just, having to find out that the whole reason no one else was concerned was that they _already knew_ was really embarrassing. Larkeet laughed at me, but that's just her, I guess."

"I swear, had I known it was that big of a deal, I would have told you. I guess he and I just didn't really plan on anyone finding out directly basically just because we didn't want anyone upset."

"Whoops."

"Whoops," he agreed.

"Well, I guess I'm done being upset, at least. Thanks for hearing me out. And I'm sorry about the AIRHORN, it was petty."

"Nah, it's fine." _My head is killing me now, but it's fine._

"It sounds like you really love him," she said, leaning back against the desk.

Sans felt a sudden chill in his bones. "What?" he asked.

She cocked her head to the side. "Well, it does. Is that- I mean, am I wrong?"

"I don't... know?" Sans wondered briefly if someone could have turned off the oxygen in the room, if maybe that was why it was suddenly so hard to breathe. His pulse was racing.

"Woah, are you okay, Sans?" She took a tentative step toward him, holding her hands in front of her.

"Yeah, I just," his head was swimming, and he blamed it on the hangover. "I guess I haven't given it much thought." Playing it cool was ten times more difficult when you were dizzy, that was a scientific fact. "I mean yeah, we're dating, but uh, I've never really... shit, now I'm gonna be thinking about this."

"Hey, it's fine if you don't, Sans! I was just saying that's what it sounds like to me. Don't overthink it, okay?"

"Yeah," he sighed. "Yeah, I won't. No worries."  
  
From the lobby, he heard Wickett yawning, then footsteps, and the sound of the elevator doors.

**Notes for the Chapter:**

> Okay but here's a shoutout to all those folks out there who use their position of power to take advantage of someone else: fuk u


	46. Overthinking it

Sans met Wickett in front of the elevator doors as they opened to the lab proper, startling him immensely.

"Gah!" Wickett shouted, clutching his chest, "Jeez, I forgot you could do that!"

"Sorry. Really sorry, but hey," Sans took a step forward. "I gotta ask why you were listening in on a private conversation like that."

"I wasn't," said Wickett, straightening his collar, "I was dozing off. And you've got to learn that the lab isn't your personal playground. If a conversation's really that private, you can have it elsewhere."

Sans scoffed. "I - Okay, no, you've got a point there, but you still-"

Wickett cut him off with a gesture, then placed both hands gingerly on the skeleton's shoulders. "Listen, please, because I don't know how many more times I'm going to have to tell you this: I don't care about your love life, or your little office drama. I'm not going to tell anyone, because I want _no involvement whatsoever_. It'd honestly be great if you could just keep this kind of thing outside of the workplace, but knowing Dr. Gaster's level of professionalism, that's asking for a lot."

"What about June's story? you won't-"

"Also not my business. I may be a gossip at times, but I know when something shouldn't be spread around. That's more Dr. Larkeet's jive. Now, if you'll excuse me, I'm sure there's some work I could be doing." He released his grasp on Sans's shoulders and turned away, walking down the hall without another word.

Sans sighed and slumped against the wall, taking a moment to nurse his headache, and clear his head. Thoughts of what June had said were rushing in, once the threat of Wickett blabbing about their little talk had been taken care of.

He slid down onto his backside as his pulse raced. _Do I love him?  I can't possibly, Can I? It's way too soon, and I've never..._

The elevator dinged, jarring him from his thoughts as June stepped forth.

"Um, You okay?" she asked, holding out a hand to help him up.

"Yeah, I... Yeah." He hesitantly grasped her hand in his and let her pull him up. "I might be overthinking things a little. What're you doing down here?"

"I miiiiiight have lied to Dr. Gaster about having work to do, so I'd like to see if there's something I can do down here instead."

"Alright, well I think he's in his office. I might as well go, too."

* * *

  
"So... this is it."

"Woah," Larkeet whispered. "Can you just," she stretched out a wing toward the void, "just walk right in then?"

"It wouldn't harm you, I'm sure," Gaster told her, "Though the increase in air pressure might be uncomfortable at first."

She shakily probed into the darkness with one limb, before taking a step forward and poking her head in a few inches. Her feathers puffed up and she shivered, pulling away immediately. "Ohp, nope, I don't really care for that," she said, preening them back down slowly.

Gaster chuckled. "No, I didn't think you would." It had taken some time to decipher his drunken scribblings all over the crumpled napkin, but Gaster eventually got his points across to her on what he and Sans had accomplished. As for the void itself, he figured the easiest thing was just to show her.

"Well, that's pretty damn wild." Came Wickett's voice from the room's entrance, "What is it?"

Gaster rolled his eyes, "Alright, I'll explain it again."

Not two minutes into his explanation, Sans and Juneborg showed up. "Woah," said June, "What is that??"

"Okay, from the beginning," he rubbed the side of his forehead with one hand, not that it did anything to soothe his raging headache. "For the third time..." He paused when he heard Dr. Larkeet snickering next to him. He scowled down at her. "If you're finished," he offered.

After making it all the way through his explanation of the void, (this time with Sans's help) he began to wonder if it might be a bad idea to hold the door open this long.

"Why aren't we pouring research into this?" Larkeet asked, peering into the darkness once more.

"That's not what we're being paid to do," Gaster told her, "King Asgore wants us to bring down the barrier."

"Yeah, but we're not really getting anywhere with that," she said, "And this? This is incredible! Not only a faster way to get from place to place, but time travel? Like, are you kidding me, Asgore would be all over this!"

"She's right," said June, "Not to mention we've got extra time on our hands, since we need to wait before we can fire the cannon again. And like, we already know what the problem is, there. We're not really doing anything more productive, right now."

"June's got a point there, Doc," said Sans, shrugging.

"We can't just start looking into random things while on the clock without Asgore's permission," Gaster insisted, "Not something as big as this, anyways. We need accountability."

"Pfft, as if you haven't already been doing that the whole time you've worked here," muttered Wickett. "If it's that big a deal, why not tell him about it and see what he thinks?"

Gaster blushed in response. "W-well, we don't know enough about it, to bring it to his attention, really. Sans and I have just begun figuring out this whole thing, and we don't have any solid, documented data..."

June rolled her eyes. "That's circular thinking," she groaned, "If you need some data, _get_ some data, then show it to Asgore, let him flip his shit, and get _more_ data with his permission. At this point, anything's better than pouring weeks' worth of work into false hope and a blackout."

Gaster stared at her, aghast.

"Or, you know, whatever." She folded her arms and leaned away.

"Right, well, I'll give it some thought," the doctor muttered, closing the enchantment next to him. "There is still much about the void we don't really know, so I suppose there is just that much more to discover. I'll ask Asgore about looking into it in our downtime, but as of right now, the cannon is still our top priority. Our second priority is making sure the lab is in top condition during our downtime, since we don't normally have this much free time to spend on maintenance."

"If I may," Wickett cut in, raising his hand toward Gaster, "I believe I have a lead on something regarding the barrier, something we discussed previously? I'd like to keep looking into that while I've got the time."

"Fine," sighed Gaster, "Fine. I'm going to reorganize my- I'll be in my office."

He dismissed them all with a wave of his hand, and shut the office door behind him, waiting for them all to take their leave. Surely they would find something to do. His head was killing him, and secretly he was hoping to take a nap behind closed doors. Perhaps a wild night out followed by another wild night out only a few hours later wasn't the best idea. He sighed and flopped down on his cot when he heard a knock at the office door.

"Yes?" he called out, too loudly for his own liking. Sans slowly opened the door and stepped in, closing it behind him immediately.

"Hope I'm not bothering you," the young skeleton muttered, "Just wanted to see how you were holding up."

For some reason his face was completely flushed, which Gaster enjoyed more than he would ever admit, though he wasn't sure of the cause this time.

  
"I'll live," Gaster said, "though I'm considering brewing up some of that tea you gave me, the one that relieves headaches. I'd stick to my usual methods, but I'm absolutely not feeling up to it." He gave a weak wink, and a wry smile.

Sans chuckled and joined him on the cot, scooting in close. "I'll make you some," he offered, "if you let me take a quick nap in here with you."

Gaster put one arm around him and pulled him closer, relishing his warmth. "Deal," he said, simply, already beginning to doze off.

The two of them were woken within the hour by loud knocks on the office door. Gaster groaned and rolled over; Larkeet must have figured out that neither of them were working.

* * *

  
The day had gone by far too slowly for Sans's liking, with almost nothing to actually do, and a raging headache. He had learned his lesson about drinking heavily when he worked the next morning, and wasn't likely to repeat the mistake any time soon.

So, feeling unwell, and being bored out of his skull, it made sense that he was more than ready for the day to be over. But when he rushed out of the lab at closing time, (after giving Gaster a quick kiss goodbye) he had other things on his mind. He called up his mother as soon as he knew he was alone, and nervously held the phone close, praying she picked up.

"Mom?" he asked, when he finally heard her voice on the end of the line, "Hey, it's me. So uh, don't freak out or anything, but I could really use your advice right about now. Is it alright if I come over?"


	47. Onions and Garlic

**Notes for the Chapter:**

> Isn't it great when chapters are conveniently flavored?

It was Papyrus who answered the door, with plenty of cheer.

"Oh, Good evening, Sans! Did mother invite you over for supper tonight?" he asked, "Because it won't be ready for a few more hours."

"Nah," Sans said, stepping past him, "I'm just here to chat. How are things going?"

Papyrus shrugged. "Alright, I suppose. Everyone's busy getting ready for graduation, myself included. And how are you doing, Sans?"

Sans shrugged back. "Spiffy, I guess," he said, simply.

"Wonderful! I'm certainly glad we had this chat!"

"Heh, me too. So um, where's Mom?"

"I'm in here!" Verdana called from the kitchen. Sans walked in to find her seated at the table, scowling at the pages of a thick cookbook. "Sit down, Sweetie," she said, without looking up.

Sans pulled out a chair at the table and sat down slowly scooting himself in across from his mother. Papyrus followed suit, resting his chin eagerly in his hands as he leaned onto the table.

"So," said Verdana, finally bringing her gaze up to meet him, "What's going on?"

"Not much," Sans said, nervously. His eyelights flicked quickly over to Papyrus, who he wasn't sure he really wanted to be part of this conversation. Things were embarrassing enough with just one audience member. "I uh, was hoping to get some advice... on something..." Fuck, he was faltering already. It hadn't been a good idea to come over here. He didn't want to turn his brother away from the conversation, but it was going to be hard enough talking to Verdana alone about this without Papyrus's input.

Lucky for him, Verdana seemed to pick up on this. "Papyrus," she said quietly, "Would you mind giving us some privacy?"

"Sure!" he said, standing up quickly, "I should probably start on my homework, after all."

"Thank you," said Sans, to both of them. He slumped onto the table once Papyrus was out of the room, laying his face over his arms.

"Is everything alright?" Verdana asked, quietly.

Sans sighed. "Yeah, but..."

"Are things going well with work? With," he could _feel_ the weight of her pause, "Dr. Gaster?"

He righted his posture. "Yeah, things are going great. Well, not great, not with work. You know, the whole catastrophic failure thing that took the whole weekend to fix. But things are going well with Gaster. _Really_ well. Just..." he felt himself sighing again. "Just about everyone we work with managed to find out about it, and someone said something-"

She shifted in her chair. "Is someone upset at you?"

"Not exactly. I think they're all varying shades of annoyed. I mean, one of them was upset, yeah, but over kind of a misunderstanding. Anyway, she said something that was probably completely innocuous in hindsight, and then told me not to overthink it, but here I am and..." he took a deep breath, steadying his pulse. It was best just to come right out with it, he decided. "Mom, how did you know you loved Mol?"

For a moment, her only response was a small, sharp intake of breath as she leaned back. Apparently the question had caught her off-guard. Sans hunched in on himself, regretting his choice in bringing the conversation to topic.

"I knew," she whispered, "back before we even started dating. I loved her as a friend, first." Her eyelights were dim and unfocused, a sure sign that she was deep in her memories, slogging through thoughts that she now kept at arms length. She looked down and sighed, visibly clearing all those memories away again to deal with the task at hand. "So," she said quietly, leaning forward, "You think you're in love?"

He slouched further, looking away. "I don't know," he admitted, "I've never been in love. I haven't even had a serious relationship since elementary school. We haven't even known each other that long and.. I don't want to mess this up."

  
She smiled at that. "Then don't worry about it," she said, simply.

Sans scoffed. "How can I not worry about it? I mean loving someone is the difference between a short, casual, forgettable relationship, and something... real, something permanent."

"Sans, 'I love you' doesn't mean it's going to last forever," she warned, her voice weary, "Every relationship comes to an end, eventually, no matter how much people love each other."

"Shit, 'm sorry," he groaned, gritting his teeth. He was slowly becoming an ace at making his mother uncomfortable.

"If you spend the whole time worrying about whether it's 'really love', or if it's 'really real'... If your mind is elsewhere, you're just gonna give yourself a bad time. Him too, probably. A relationship should be something you don't agonize over, it should be an experience. Ideally, a pleasant, healthy experience but the world isn't perfect. Ride it out and see where it takes you, Sweetie."

"But what if it takes me to- what if... what if I eventually do realize I love him, and _he_ realizes he doesn't feel the same way?"

She smiled wryly. "At that point you just gotta sit down with him and talk it out, discuss whether the relationship is worth having. It doesn't sound like fun, I know, but you're both adults, and it's way better than torturing yourself, trust me."

He sighed in relent.

She sighed as well. "If you really want to know, Mollig and I hadn't been friends very long at all when I realized I cared about her deeply, and would do just about anything to make her happy. I wanted her to be happy. Of course, her friend, who shall remain nameless, had other ideas, and things got rough. She was at a low point, and she told me I didn't have to stick around, but I wanted to, because I wanted to be there for her." Verdana smiled fondly as she spoke, but the lines under her eyes just made her look wistful and sad. "I stuck with her, and eventually, the love I already felt for her just kind of turned into something a bit more romantic, you know?"

"Sounds like it was nice," he muttered quietly.

"It was. We were happy together, we loved each other so much. I still do... love her. And that makes it hard, sometimes. I know I've been a little distant about it, all this time. But maybe some day you'll under- well, no. I hope you don't ever know what it's like... The more you love someone, and care about them, and build your life around them, the more it hurts to lose them."

Sans felt a tightness in his throat. His eyes burned. "I'm sorry, mom," he said.

She laughed loudly, her voice thin and watery. "Oh, listen to me, I'm depressed! Wow, do me a favor and lock up the liquor cabinet, tonight eh?"

He forced out a quick, dry chuckle. It wasn't entirely a joke. "Yeah, sure. I'll do it after dinner."

"Riiight, shit." She pushed her chair back and leaned on the table for support as she stood up straight. "I need to get on that, like, now. Do me a favor will you? See if your brother needs any help with his homework? I've got to, um," She scanned down the page she had left the book open to, "Onions."

"Yeah, okay. You go ahead and 'onions', then," he said with a smirk.

"Oh, um. Sans? Ignoring my bias against the man for a moment... if you care about him as much as you care about Papyrus, or myself, or any of your friends... then _why not_ tell him you love him? I mean, love comes naturally to us, as monsters. if you can love your friends, and love your family, why not just... love the person you're with? If it turns out later that you don't... well, then you just cared about him a little less than you thought, right? Still more than he deserves."

Sans laughed. _Not biased at all_ , he thought. "I'll think about it. But uh, not _too_ much. I think, when we've known each other a little longer, maybe then."

"Good plan."

* * *

 

Gaster stood against his kitchen counter, trembling. He had absentmindedly poured an entire container of dried garlic into his oatmeal, but that didn't matter. What mattered was that as his mind had been allowed to drift, finally free from the burden of the most powerful hangover he'd had in half a decade, he had begun to think over the events of the previous night, in its entirety.

Some patches were still hazy, or missing entirely, but one thing stood out clearly in his mind.

Three things. It was three words, after all. His cheeks began to burn.

"Fuck!" he muttered, smacking his forehead.

"I was going to wait until I was sure he... damnit! It was supposed to be special, not some drunken slurry uttered moments before losing consciousness. This isn't fair! He probably doesn't even... Oh!"

If Sans didn't remember, then there was nothing to worry about! But if he did...

"If he hasn't brought it up, I'll have to assume that he has no recollection. Perhaps he thinks it was a dream. Or, _perhaps_ I made him feel rushed and uncomfortable, and he'd rather not bring it up until he's ready. Either way, I suppose I'm in the clear for now, aren't I?!"

In either case, it was way too early for him to be making such a statement. He didn't want to push Sans away, did he? He would need to wait, and try again later. If Sans was avoiding the topic on purpose, then it would give him time to think it over. If he was unaware, it would give Gaster time to plan for a possible fallout. Win-win!

He cackled and pressed his hands over his face, using his index fingers to massage deep circles into his temples, a futile effort to drive away a looming migraine. He needed to stop being stressed. Or find more temporary relief. Later.

The stench of all that garlic finally began to take its toll, and he decided to clean it up before it became a problem. It certainly wasn't helping his migraine, after all.

The problem with waiting, he realized as he was scrubbing his bowl clean, was that in the mean time, Sans might not _know_ how Gaster felt about him. He felt a tightness in him, at that thought. Maybe that was better than knowing and not caring.

Gaster groaned and left the kitchen quickly. _Screw the oatmeal,_ he thought. _I'm a grown man, I shouldn't be so affected by this_.

He threw himself onto his bed face first, grabbed a pillow, and shoved his face into it carelessly.

Muffled though they were, he repeated the words to himself, thinking back on the previous evening.

It felt nice, just to say them out loud.

**Notes for the Chapter:**

> "The L word is coming," they said.
> 
> "I feel it," they said.
> 
> "I'm so excited for the I love you's" they said.
> 
> Little did they know that Sans and Gaster would accidentally conspire together to drag that wait out as long as possible.
> 
> Whoopsie-doodles!


	48. Nerd Day

**Notes for the Chapter:**

> Thank you for your patience. Again. We're closing in on the end of this story, and I'm trying to make sure EVERYTHING'S at least a little wrapped up. Two chapters to go, after this one! Yee haw!  
> [By the way, I forgot to share this sexy (NSFW) Gaster Trisaffritops drew!](http://trisaffritops.tumblr.com/post/150895681681/i-know-ive-been-promising-you-guys-a-comic-based)  
> Give him some love for me, would ya?

Gaster made sure to call Asgore the next morning and ask him, just to be certain, to be safe, whether he and his team should be looking into something completely unrelated to their mission of bringing down the barrier.

  
"Just until we're ready to fire the cannon again," Gaster assured him, "We're still set to go at the end of next week."

  
King Asgore Dreemurr said 'sure'.

  
And that was that.

  
He gave the news to Sans first, pulling him aside in the early morning. To his surprise, Sans was overjoyed.

  
"Thank god, I mean this week has been exciting in more ways than I can count, but I kinda like having something to _do_ , you know?"

  
Gaster shrugged. Two weeks worth of busywork and spring-cleaning while they prepared for Round Two _was_ technically something to do, but even he found it incredibly boring.

  
"Besides," Sans added, "that little blue paper said to ask for help, but it didn't say you could only ask one person. We're that much closer to figuring this all out, but I don't think I have all the answers you need. Maybe someone else on our team does."

  
They all had ideas, that was for sure.

  
"As your assistant, I feel compelled to tell you that your note-taking skills could use some fucking improvement," Larkeet told him, laying his notes out on the table in front of her.

  
"Is that your _professional opinion_?" he asked, keeping his eyes locked o on the papers he was holding. If he looked up, if he looked angry, she would win.

  
"My professional opinion is that there's no point in taking notes or making records that you can't utilize later. Half of this is disjointed or down right illegible."

  
"All of my notes and data regarding the **cannon** are legible and organized. This was something done in my free time, mostly for my own benefit. Had I known you were going to hold me under scrutiny, I would have done better."

  
"Pfft."

  
"Right back at you."

* * *

  
Still, they managed to organize what he had collected so far, and it was enough to give them a head start, and help them figure out exactly what they still didn't know about the void.

  
Which was most things.

  
They decided to narrow it down to a bullet-pointed list, with space to write in more questions as they solved previous ones.

  
For example, _who_ could open up a doorway to the void? To their knowledge, only Sans, Gaster and the dog had figured it out so far. Which led to a new question: _Why_?

  
"This shouldn't be so difficult," Wickett snapped, failing for the third time to copy Gaster's enchantment. "I mean, it's complex magic, sure, but there's got to be some trick to it."

  
"Maybe it has something to do with my natural affinity," Gaster suggested.

  
"And what affinity is that?"

  
"I never quite figured that out," he admitted, "I know for sure the **hands** are a family construct, but this..."

  
Wickett dissolved his attempted enchantment. "Also wouldn't explain why Sans can do it so well."

  
Sans shrugged. "I've got a knack for copying magic, I've never had to think too hard about it."

  
"You should look into magical theory," said Wickett, sternly, "Having a knack for something's not going to do you any good if you don't even uderstand what you're copying. Not to mention you're bound by the limits of the monster you're copying from." He flicked his eyes over to Gaster, not long enough to catch the doctor glare back at him.

  
Sans held out his hand and instantly opened up a doorway to the void in the space Wickett had been trying. "It's done me just fine so far," he said with a smirk.

  
Gaster's body shook with silent laughter as Wickett's flame popped and sparked in indignation.

  
"Anyway," Sans continued, "My affinity, Gaster's affinity, yada yada. What about the dog? That little fucker's been jumping in and out of this space since before any of us even knew it existed. I think if anything needs explanation, it's that."

  
"The dog's... not a normal monster," Wickett said slowly. "But now that you mention it..." He trailed off and turned away from them.

  
"Continue?" Gaster prompted, snapping his fingers.

  
"I'm still looking into it," he admitted, walking away slowly, "but there's a component there, I know it."

  
Sans held his hands up in confusion, squinting at Wickett's back as he ambled away.

  
Gaster sighed. He knew, at least, what component the professor was referring to, but had yet to figure out how a similarity to the human souls came into play here, and how it affected either him or Sans.

  
After all, it wasn't as if Determination simply rubbed off onto every monster the dog came into contact with.

  
After Wickett, Dr. Larkeet had come the closest to actually opening the void.

  
Sans joked that maybe being a physicist made the difference.

  
Gaster's notes simply stated that multiple factors must come into play, and that there was insufficient data to conclude exactly what those factors were.

* * *

  
"We have no idea how to navigate in the darkness of the void," Gaster had said.

  
"Sound waves." Juneborg offered, not even looking at him. Instead, she reached into her lab coat pocket to pull out an **AIRHORN** , held it just outside of the open doorway, and pushed the button.

  
Gaster winced at the loud blast of noise. Was she just carrying that thing everywhere, now? he'd have to think of some way to confiscate it.

  
"Like that," she said, returning the _AIRHORN_ to her pocket as the echo died down. Gaster would swear the even, steady rhythm of her clicking mandibles and the way she stared right at him was a sign that she was still bitter about not being let directly into the void under any circumstances. He scowled back. It wasn't his fault her body relied on electricity.

  
"Our sonar equipment is a little outdated," Larkeet had countered, "I'm not even sure it works."

  
"So, I can build something new for us, something we can use from outside the void itself," said June. "It'll be a snap."

  
He had expected that to be an exaggeration but by late the next morning, she had something ready. It looked like a toaster oven mated with a vacuum cleaner and their baby ate a television.

  
"I used one of the old machines I found hidden in a back room," she explained, "and I built on that. It's not pretty, but it was able to accurately map out my apartment building, and the lower lab here." She yawned. "Can we test it out today?"

  
Everyone agreed that 'immediately' would be the best time to try it out. She handed the end of the probe to Sans, who set it up just inside the entrance to the void while she hooked her machine up to Gaster's computer. They all huddled down by the monitor as she prepared to set it off, demanding silence from each of them.

  
A loud, wavering sound fired out from the end of the probe, and they listened closely as the echoes rang out.

  
Fifteen long seconds passed before the echoes died down completely, and they all watched in awe as a vast tangle of long, winding, branching paths spread out on the monitor before them.

  
"It looks like a tree," Larkeet whispered to Gaster.

  
He partially agreed. One major difference between the heinous mess before them and an actual tree was that a tree would 'branch out' at both ends, both its roots and branches spreading and splitting in all directions.

  
This example only continued to branch out on one end. At the other end, lines and paths seemed to just keep converging and joining, with some strands woven around each other, or even looped back on themselves.

  
"If this is a map of what I think it's a map of, then this..." said Gaster, pointing to the converging end, "Would be the past, continuously branching out toward this," he slid his finger over to the splitting end. "Infinitely branching possibilities, of an endless future... or so the theory goes."

  
Somewhere off in the distance, there was a major fork in the paths, with some continuing on in the normal pattern of twisting and splitting and looping. The rest was a mess, a horrid knot of strands that looped and looped and looped onto each other, moving steadily toward what appeared to be a singular dead end.

  
"Nothing's displaying past that point," muttered Wickett. And true, though other paths continued to branch out, continuing to move steadily forward, past that singular point, every other path was severed.

  
"Maybe that's just the end my machine's reach," June offered, reassuringly, "I mean, this is a huge amount of data as it is."

  
"Ordinarily, I would agree with you," said Gaster, "But if you'll notice- the map spreads much further in one direction than the other, and along that end, things slowly fade out. That would probably mark the limit of your machine's capability. But this... **anomaly** , or whatever it is... I'd estimate we're much closer to that end of the line than the other. That's troubling, to say the least."

  
A heavy silence fell over them as they stared at the flickering screen, soaking in the mysterious image.

  
Gaster was the first to shake the silence off.

  
"So, do we- Can we try this again, but with me in there?"

* * *

  
By the end of the day, they had retried the map-making process around twelve different times, with assorted variables changed each time. The size and shape of the map never changed, but they were able to pinpoint their location on it, based on the little blip that represented Gaster, which never changed despite his location within the void itself.

  
So, Sans reasoned, while time and space were connected in the void, they probably weren't as directly connected as any of them had thought. It made sense in hindsight, he supposed. He and Gaster (and the dog) were able to move freely around within the void, as well as jump from one place to another _through_ the void, without actually having to travel the exact distance it would take otherwise. And yet, they were able to travel through time by moving through the space of the void, also.

  
"Wait, wait, but there's a difference!" he continued out loud, to the bemusement of those around him. "Oh, sorry. Heh."

  
"Care to share your revelation with the rest of the class?" Larkeet asked.

  
"I uh. Think there might be a key difference between the times we've just traveled through the void, and when we've traveled through time."

  
"Go on," Gaster prompted.

  
Sans touched his fingertips down to the surface of the desk, and slid them in a slow, curving line as he spoke. "So, I think intent matters, first of all. Because when we go through the void with the intent of getting somewhere else, we travel along a flat plane from point A to point B, no matter how many turns it takes or where we go in the void, we come out shortly after we left, in a linear fashion. But," he raised his hand to point at the image on the screen, "That mess doesn't move along a flat plane. There's dimension, lines loop over and under each other. And the times we've ended up some- _when_ else? We've fallen, or jumped, or were dragged through."

  
"We might have detatched ourselves from the spacial plane," Gaster mumbled.

  
"Exactly! So while velocity might come into play here, I think direction AND dimension do, too."

  
"Do you think velocity has any direct effect on how far you travel through time?" asked Larkeet.

  
"No idea," said Sans, "But I think we can find out!"

  
"Not today," said Gaster, "it's getting late as it is, and while I love the idea of staying late, we have tomorrow and all next week still, to figure this out."

  
There was a disjointed mumble of agreement from the rest of them. Sans sighed, still high off the excitement of discovery.

  
Gaster closed the door to the void and the whole group made their way up to the lobby, chatting excitedly in the elevator, speculating just how far back the map might go, if they had the capability to see that far.

  
"I'll try and make some improvements to the hardware we're using," said June, "And see if maybe we can find out."

  
Sans made sure he and Gaster were the last two in the lab, ignoring smug looks from over the shoulders of his coworkers as they each headed out the door.

  
"So," Gaster began, grabbing his attention, "This is progressing."

  
His grin widened. "It sure is," he said, "Nervous?"

  
Gaster shrugged. "A little. If that map is in any way an accurate portrayal of branching timelines... for them to just end like that is more than a little concerning, don't you think?"

  
"Yeah, don't worry, though. We'll get it figured out," said Sans. He shoved his hands in his pockets. They would obviously have to get it figured out at _some_ point, if there was to be a complete time loop on Gaster's end. "Hey, wanna come over tonight? I could make dinner or something."

  
"I'd love to."

  
"I-" Sans held his breath in a desperate attempt to keep calm. Had he heard that right? He needed to say something, now!

  
No, wait, Gaster was just agreeing to come over. "Cool." He sighed to quell the rush that had almost overtaken him. He had just about steadied himself, when he felt Gaster's arm wrap around his shoulder, and he tensed again.

  
"Are you alright?" Gaster looked down at him, concerned.

  
"Yeah," he realized, at the same moment he said it. The tension fled his body, and he leaned into Gaster's side. "Let's go."

* * *

 

On Friday, Alphys greeted them with more cheer than Sans figured she'd be capable of, after a week's worth of AP finals. Sans had to commend her on that.

  
"Good morning!" she said, flashing what he'd bet was her first smile that whole week, "What did I miss?"

 

Oh boy.

  
"Alphys, buddy," said Sans, "Lemme tell you. A _lot_."

  
"Um."

  
He poured two cups of coffee, pulled her aside, and explained the happenings of the week, sparing no details. If she was finally done with school, she'd probably be at the lab more often from that point, and it was only fair she be brought up to speed.

  
"Congratulations on your graduation, by the way," he added, before draining the last dregs of his coffee. "Shouldn't you be out celebrating?"

  
"I CAN'T BELIEVE YOU AND DR. GASTER ARE DATING!" she shouted, as if that was the most important revelation, and not the fact that he and Dr. Gaster were time-traveling. "How long have you been dating?" she asked.

  
He pretended to take another sip from his mug. "A while."

  
"Oh my god."

  
"So uh, anyway, I should probably get to work. There's lots going on right now, despite the fact that we're technically on hiatus. If you're looking for something to do, Wickett's still studying dog-sweat, and June's trying to improve her little invention. I think Larkeet and Gaster are compiling the maps we made yesterday, and there's a broken oscilloscope with your name on it. Or you could help me."

  
"W-what are you doing?"

  
He grinned. "I brought a bag of tennis balls with me to work today, and I'm going to number them, and throw them all into the void in different directions, at the same speed. Then, I'm gonna try to guess where- and _when_ , they'll end up. And I've gotta check them for dog slobber, because if that mutt gets to them, it doesn't count."

  
"Oh!" her face brightened, "I know how to make simple tracking devices, would that make things easier?"

  
"Yeah, actually. Jeez, Welcome aboard, Dr. Alphys."

  
With a full team, and plenty to do, things were looking better than ever.

**Notes for the Chapter:**

> Next chapter's a smut chapter, btw!


	49. Under

**Notes for the Chapter:**

> Smut chapter ahead, NSFW, be forewarned.
> 
> Next chapter should be the end.

After a few uneventful days, Gaster breathed easy. _All excitement and discovery, no cool-down period, makes Jack tense and wears him out_ , as the expression went. Still, treading the fine line between relaxation and boredom was a challenge.

 He couldn't have boredom, because boredom lead to laziness, and mistakes.

 Like not paying attention when you get dressed in the morning.

 Gaster could see it from all the way across the lobby, but looking around, his cohorts didn't seem to have noticed yet. He bid them all good morning, and waited for Sans to approach the coffee station before tapping him on the shoulder. "You seem to have missed a button," he murmured discreetly, pointing at the middle of the skeleton's shirt. In fact, the entire top half of his shirt buttons were misaligned because of it.

 Sans looked down to confirm that this was true, then blinked blearily back up at the doctor, a sweet smile spread across his face. "Woah, sorry about that. I didn't get much sleep." He began to correct his mistake, unbuttoning everything from the middle upward. Gaster sighed and positioned himself as best as he could between Sans and the rest of the lab, hoping to block the view. He was about to avert his own gaze when his eyes caught a flash of color where the dull white of Sans's ribs should have been. He turned back just in time to see some shimmering purple fabric being quickly covered up as Sans rebuttoned his shirt, all the way to the top.

Had he seen that right? _Satin?? Or was it silk?_ His eyes made their way up to the skeleton's face, where the sweet smile from earlier had been replaced with an impish grin. "I'm so glad you caught that," Sans said with a wink, "who knows **what I'd've done with myself** if you hadn't." He fastened the topmost button, right under the collar, then grabbed his coffee and turned away without another word, making his way up to the office.

Gaster remained where he was, dumbstruck. From what little he had seen, it looked like lingerie. That had to be a mistake. Why would Sans be wearing lingerie at work? His heart began to race, thinking about it. Was he being toyed with?

Taking a few moments to regain his composure, he followed up to the office area.

"What was that?" he whispered, leaning over the back of Sans's chair.

"Hm?" Sans didn't even look up at him. "You need something?" he asked.

"Good morning, Doctor Gaster!" Juneborg called from the top of the stairs, behind him.

He straightened up immediately, pulling away from Sans. "Good morning, Juneborg," he called in return. He waited for her to sit down before trying again. "Sans, may I speak to you in my office for a moment?"

"I'm actually kind of busy," Sans said, finally turning to look back at Gaster. "Can it wait?"

"I..." Gaster caught June's head turning toward them, just the slightest bit, "Of course. Just, come find me, when you get the chance."

"Will do," said Sans, "might be a while though, just a head's up."

Gaster waited over an hour, trying to keep himself occupied with work while his mind was elsewhere. Finally, two knocks sounded at his office door. "Come in," he answered quickly.

Sans only opened the door partway, and only leaned in, wrapping himself around the doorway. "What's up, Doc?" he asked.

"Please come in and shut the door."

"What for?"

" _Sans._ "

"Yeah, ok." Sans did as he was instructed, but hung back, near the door. "What's up?" he repeated. Gaster noted that the topmost button was now undone, his neck exposed as it usually was.

Gaster beckoned him over with one finger. "I want to know what you're wearing under that shirt."

The faintest bit of color tinged Sans's cheekbones. "A surprise," he said.

"Let me see. Please."

Sans took a few slow steps toward Gaster, keeping only an arm's length between them. Gaster watched the skeleton's hands move slowly upwards, redoing the topmost button. "Not here," he said, quietly, "You free tonight, after work?"

"I am now."

"Cool." Sans leaned in and pressed a kiss to Gaster's cheek, keeping his hands on his collar. Gaster's skin felt hot at the point of contact. "After work, then."

It was shaping up to be a hell of a long day. Gaster found he could hardly focus, his thoughts shifting continuously back to the brief glimpse of whatever it was Sans was hiding beneath his clothes. _A surprise_. He found himself imagining various forms of lingerie, lovely fabric and lace clinging to Sans's near naked form.

One thing was for sure; the hours of a day did not pass more quickly when one was looking forward to something. And Sans wasn't making it easy on him, flashing him smug grins and winks throughout the day. At one point the doctor found himself leaning forward in his seat, absently rubbing his legs against himself. He corrected his posture immediately when he realized what he'd been doing, thankful there was no one around to catch him.

Ten minutes before the end of their workday, Sans confronted him. "Hey, Doc, I was thinking of asking everyone out for drinks before we-"

"Sans," Gaster begged, closing what little distance there was between them. "Just show me, please."

Sans laughed, leaning into him. "Alright, alright, no drinks. I'll be on your bed then." He stepped away and into the void, disappearing from sight.

Gaster considered staying for the remaining nine minutes of their workday, but realized that letting Sans have that kind of head start was something only an idiot would do. He took a deep breath and followed into the void, stepping into the hallway of his own home. His bedroom door stood ajar, and he peeked through the opening to find Sans sitting on his bed, pants and shoes strewn aside, slowly kicking off his socks. Gaster pushed the door open slowly, staring his lover down from the doorway.

"Come on in," Sans said, leaning back. As if it was his permission to give. Gaster remained where he was, leaning against the frame of the door, watching him. His pulse was racing already, seeing Sans in what appeared to be nothing but a shirt, bare femurs spread apart over the duvet. He caught another glimpse of dark purple, poking out from under the hem of the shirt.

He felt a heat building within himself, something rising and pushing all the air out of his lungs.

"You wanna see?" asked Sans, spreading his legs further. Gaster's gaze worked its way up slowly, meeting Sans's eyes. The skeleton's face was full flush now. "It's my first time wearing something like this," he admitted, as he slowly unbuttoned his shirt.

Gaster bit his lip as what he had caught the briefest glimpse of earlier, what had driven him close to madness throughout the day, was finally revealed. Dark violet silk shimmered in the light of the room, clinging to Sans's body perfectly as he leaned back to give the doctor a better view. Edged in lace, held up by a ribbon around the back of Sans's neck, the top of the piece was low-cut, and showed off the bottom of his ribcage as well. The bottoms, a beautiful, lacy pair of silk panties, fastened from the sides to a band around the middle of his spine.

For his first time wearing something like this, Sans had picked one hell of an ensemble. Gaster moved forward slowly, and knelt in front of him at the edge of the bed. "You look beautiful," he whispered.

"Yeah?" Sans's breath shook. "You too."

Gaster laughed. Leaning forward, he kissed Sans's kneecap gently, enjoying the slight spasm he got in response. "I can't believe you were wearing something like this all day," he said.

Sans's grin returned to it's previous, impish state. Gaster felt his own cock twitch. When had he become hard?

"What'd you think it was?" the skeleton asked.

Gaster ran his hands slowly over the bare femurs in front of him, back and forth. "I wasn't far off," he admitted. Still, he hadn't pictured this exactly, so the element of surprise was still there. Nothing he had pictured had been half as good as Sans looked now. He ran his hands down the surface of the silky fabric, relishing the way it shifted and clung to the curve of each rib. Sans shivered, and Gaster leaned in to press his lips to the silken texture of the panties, right over the skeleton's pubis.

Sans swore under his breath.

Rude language had never sounded so lovely. The doctor traced his fingers over the edges of Sans's iliac crests, up over, around to his sacrum. He was met with the kind of low, raspy noise that made his groin ache. "Can I make love to you?" Gaster pleaded, breathlessly.

"What?"

Sans was staring down at him, his face tense and flush.

"I said, can I fuck you, please?" Gaster enunciated. His lover relaxed.

"Yeah, sure. I've only been waiting all day."

"Tch. You made us both wait, then." _It seems that we're dancing around the same thing_ , thought Gaster. He stood and unfastened his pants, dropping them to the floor as he pulled his shirt over his head.

Sans had moved back on the bed, and lay on his back looking up at Gaster with a reverence he'd never be used to. It have him goosebumps, watching the way the lights of Sans's eyes became bright and unfocused. He wondered if Sans knew that they gave him away.

He reached down and slid Sans's panties off to the side, exposing a conjured pussy that was wet and ready for him. He ran one finger up the length of it while he moved himself directly above the skeleton, into an optimal position.

"Brace yourself," he whispered, guiding himself to Sans's entrance.

"I'm ready."

There was nothing to brace for. Gaster slid himself in gently and gasped, relishing the static feeling of San's slick magic wrapped around him. He shifted and pulled out halfway, then pushed in again, just as slowly as before.

"Doc-"

Gaster kissed him deeply, cutting him off. He felt Sans arch up into him, meeting him at every restrained thrust. He pulled away only to pepper kisses along the skeleton's neck and collarbones, drinking in each soft gasp and shaky breath they drew out.

Sans mumbled something unintelligible.

"Hm?" Gaster asked, stilling.

"Nothing. Just- just keep going."

He did, gladly, picking up at a better pace than before. He felt Sans's soul reaching out to him, and he reached out in turn, letting himself be taken in by the blissful, intimate sensation.

Sans pulled him down by the shoulders and kissed him roughly, scraping bony fingers over the back of his neck.

He lost it, nearly collapsing when his orgasm took him over, drunk with the sound of Sans moaning into his mouth. He pushed himself in deep as he could and let go. Sans's magic spasmed around the head of his cock and the sensation was almost too much. He pulled out of their kiss and found himself shaking, gasping for air.

"You okay?" Sans asked. Was he?

"Are you?" Gaster countered.

"Heh. I think so."

San's magic dissipated, leaving Gaster free to pull away. He didn't though, opting instead to lean in for another long kiss.

"Can I stay and sleep with you like this?" Sans whispered onto his lips when they parted.

Gaster grinned. "As if you needed to ask."

 

**Notes for the Chapter:**

> By "like this," Sans had meant he'd be in his lingerie all night. It was fine, but lead to another round early in the morning when they woke up. They were almost late to work.


	50. Closed Circuit

**Notes for the Chapter:**

> Okay, this is it! The final chapter that you've all probably been waiting for! I want to take a moment to thank ALL of you who have taken the time to read this story.  
> THANK YOU, because it means so damn much to me!!!!! And extra thanks to those that left comments, whether it was critique, praise, or speculation. Those comments kept me going when i didn't think i could finish this. It's been a hell of a long ride, and to be honest, I'm kinda sad it's over. But I will keep writing more things after this, including more sanster, so please keep a look out if you'd like.
> 
> I have to admit I bit off more than I could chew in regards to illustrating scenes from this story. I'm slow. That's probably never going to change. Fuck.  
> I do have a partially-finished illustration of [Gaster and Asgore doing garden things](https://68.media.tumblr.com/f46c96bc49d7406f2b3243f884152360/tumblr_ofnxfvXCgw1tqqf5jo2_1280.png), though. And [something from last November](https://68.media.tumblr.com/706b83d847dc17a6d92a379b6daad045/tumblr_ofnxfvXCgw1tqqf5jo1_1280.jpg), back when I thought I could make this story in comic form. (spoilers: I couldn't.)

In fact, things went smoothly for a while.

The decision to tag their tennis balls with tracking devices proved to be an important one, as they would have lost the first two dozen, otherwise. In the end, they only lost four, due to the appetite of a certain canine.

The dog proved to be more of a hindrance than a help, as usual, but by tracking the movements of pilfered tennis balls, Sans and Alphys found that certain trajectories gave predictable destinations, for both time and place of arrival.

Sans found that if he threw a ball as hard as he could with his left hand, it would reach its intended destination in approximately two hours. With his right hand, the results were a little more unpredictable. Alphys's best throws were always ten minutes. Always. But that was if they were aiming for another time. tossing the ball into the void with no aim either left the ball sitting in the void, or sent it somewhere randomly in the underground. They lost one ball to the magma of hotland.

Juneborg suggested making some sort of tennis ball firing device, because their throws weren't consistent enough to yield reliable data. Gaster reasoned that as long as a predictable pattern was forming, then complete accuracy wasn't entirely necessary. Also, one dangerous weapon under their watch was enough. If a stray ball came out of the void at high speeds, whoever stood in its way would be dust.

Sans compromised and built a tiny catapult. He could easily adjust the height and angle of his trajectories, and the firing speed would be more consistant. Truly, he was in his element as a physicist.

Angle mattered, velocity mattered, and intent mattered. And he and Alphys were close to figuring out exactly how much of each mattered, when Gaster called a halt to everything.

"Alright," he declared on the following Wednesday, "we are breaking new ground, and I appreciate that immensely, but we need to pause this and prepare for our second attempt with the blast cannon."

"It shouldn't take us three days, we need to adjust our settings and we're good," Larkeet argued.

"I would like us," he continued, "to give this our full attention, and possibly get it right this time."

* * *

 

They didn't.

Not that they hadn't tried. Dr. Larkeet was sure everything would work if they were running the blaster the way they should have been running it from the start. But it simply wasn't enough; the beam hadn't made enough of an impact on the barrier by the time their power reserves ran out.

Gaster stopped the machine before they ran out completely, avoiding a second blackout.

"Again," he demanded, "Once our reserves are recharged, we're firing again."

Much to the same result. Sans counted it a stroke of luck that he was able to monitor the blaster's effect on the barrier without the oscilloscope blowing out a second time. But the effects were disappointing, compared to their first attempt.

"We've still got Sunday, you wanna try again?" Sans asked.

"I'll talk to Asgore about it."

Gaster led Asgore away from the firing site while the others stood by, unsure of what to do.

"I can't imagine the king's too happy with us, right now," muttered Wickett.

"Honestly, I wouldn't be either," said Alphys, "I-it probably looks like we don't know what we're doing."

Fifteen minutes passed before Gaster and Asgore returned. "We're going to put a hold on this," Gaster told them, "I want everything disconnected today, we can move the rest out next week."

"Wait, what's going on?" asked Sans.

Asgore shrugged. "Well, I am not going to make you all work over the weekend," he said, plainly.

Gaster sighed. "What we're working with right now isn't going to cut it, and we risk wiping out the underground's power again if we try to up the output of the cannon. If we want the results we're looking for, We're going to have to change something." He paused to rub the side of his forehead. "Probably rebuilding the core itself."

Larkeet's feathers ruffled instantly. "Are you serious?! We _just_ finished building it."

"We won't have to start again from the ground up, it just needs to be modified to take in and reserve more energy. It might take a year or two, but it's something to keep us busy."

"Ohhh my god."

"I'm very sorry, all of you. I know you have worked hard on this," said Asgore, "but I can't let you go through with anything that might cause damage to the Underground's power supply. My citizens depend on it."

"Understood, your majesty," Wickett cut in, before Larkeet could object again.

"Thank you, Asgore," said Gaster, "Now, if you'll please excuse us, we have some work to do. Again, I'm terribly sorry for wasting your time."

"Not at all, my friend. Good luck, and enjoy the rest of your weekend. Let me know if you need anything." He offered them a sad smile, and left.

The crew set about disconnecting the cannon and gathering up their equipment, under Gaster's orders.

"So, what happened?" Sans asked, looping a long cable over his shoulder.

"I... well, mostly, I apologized for yet another error in judgement," Gaster told them. "Honestly, this _should_ work, somehow. But within the parameters we're working under, even with the massive amount of energy the core takes in... we can't use enough of it to accomplish anything without pulling another blackout, or risking damaging the power grid itself." He sighed, his shoulders lowered. "If we didn't have the entire population of the underground relying on that power system, it might be doable. But as it is..."

"You gotta consider the size of the population, too," Wickett added. "If you consider the theory that monster magic is what's keeping the barrier up and going, the recent increase in population means it may have gotten stronger as the years go on."

"Yes, thank you. I think Asgore understands that it may not be feasible, but if the population is going to continue to grow, then an addition to the core... maybe another few generators, and a stronger energy reservoir... well, maybe that'll be good for us in the long run."

So they were planning on there being a long run, now.

There was a loud clattering next to them, as Juneborg dropped the tools she had in her arms. "So that's it?" she demanded, "We're dropping the cannon, and going back to working on the core?"

Wickett squinted at her. "Isn't that where you thought you'd end up, anyway?" he asked.

"We're not dropping it completely, we're _shelving_ it," Gaster explained. "I know it's disappointing. Believe me. I know. But Asgore insists, and in the end, his word is law."

He stopped for a moment, turning his attention to the low light filtering in through the barrier. "It _can_ work," he insisted, "Human magic is tricky as hell, but it's not unstoppable. We just can't bring it down with the tools we have now. I'm sorry that I thought otherwise, I was eager as anyone is to get out of here." He turned back to his crew, staring them down. "On average, we only see a human in the underground once every thirty years. Now, that's not an absolute, but we have time to get this right."

There was an ambiguous, disappointed murmur of agreement among them.

"Remind me to show you four around the core some time next week," said Larkeet, addressing Alphys, Sans, Wickett, and Juneborg. "You'll probably need to familiarize yourselves with the layout at some point."

Sans offered to take anything important back to the lab right away, and lock up while the rest of them said their goodbyes for the day and headed home. He briefly considered popping straight home himself, but a gut feeling told him to go back to the barrier first.

Like he guessed, Gaster was still hanging around, waiting for him. He looked tense, but smiled when Sans approached.

"Any plans for tonight, Doc?" he asked.

Gaster shrugged. "A good night's rest?"

"You wanna come over to my place? Smaller bed means we sleep closer together," he offered with a wink. "You look like you need it."

The doctor turned away. "Another time, perhaps? I think I need to get this sulking feeling out of my system."

"Fair enough." _Damn_.

"Goodnight, Sans. I'll see you on Monday morning," Gaster told him, leaning down for a kiss.

"You too." A heavy feeling sank into Sans as he watched Gaster leave. He was fine, just... sad. He popped over to his own apartment and flopped onto the bed. A night alone wasn't going to do him any harm, and hopefully it would do Gaster some good.

But now he had no plans for the rest of the weekend. From his spot on the bed, he searched his apartment for something to do. His gaze fell to the books on his desk; he had library books he'd hardly touched, that were due back soon. _Maybe now'd be a good time to polish them off_ , he thought. He sat up and reached for the topmost book, a reference for learning sign language.

He flipped through the thick book mindlessly, scanning the various accompanying illustrations that accounted for many of the more common appendeges monsters posessed.

"Geez, there are like twelve different ways to say 'I love you.'" he muttered, skimming more slowly through the 'useful phrases' section.

He stopped. _Now there's an idea_ , he thought. He set the book down in his lap, freeing his hands.

"If I'm gonna learn something useful..."

* * *

  
The nice thing about the lab's new course of action was that it was going to take time to even get to the point where they could begin new construction on the core. Plans had to be drawn up, meetings had to be held, plans would then need to be revised several times, and their current crew would have to be acclimated to working at the core more directly. Then the real work could begin. That was obviously going to take months, but they would stay busy.

And, after disassembling the cannon one more time and bringing it back to the lab proper and getting it stored away for the several months it would be out of use, they had even more time to focus on exploring the void.

After a couple of weeks spent refining their experiments, Sans felt confident enough to be their 'living tennis ball', volunteering to try out their hypotheses on himself, while Gaster was away doing business.

It was easy, actually. With a running leap, he could aim himself up to six hours either forward or backward in time. Problem was, he was not an athlete, and the exertion wore him out. Also, several weeks had passed since Dr. Gaster's 'first' trip back in time. Sans sat down calculated how fast Gaster would need to be going through the void to get back that far in one jump.

_Fast._

He showed his work to Dr. Larkeet, and she nearly passed out from laughter as she pictured it.

"Oh!" said Alphys, when she heard the problem. "A few days ago, after work, um, you told me to give this to you, when you brought that up." She fished a small envelope out of her lab coat pocket, and handed it to him.

Sans opened it immediately. Inside was a folded piece of paper with his handwriting all over it.

_It's going to take a series of consecutive jumps to build up enough momentum to get you back that far. Try it, you'll figure it out. Also, give your man a kiss from me <3_

He had actually written out the _<_ and _3_ instead of just drawing a heart like a normal person. "What a fucking dweeb."

"But if you can't trust your own advice," Alphys countered, "Whose can you trust, right?" She shrugged and winked at him, in a manner that made him feel like he was being mocked.

"I guess I've got no choice but to try it."

He sealed up the letter in a new envelope and gave it a shot. It took a few tries, spread out over several days, but he _got_ it. After successfully delivering the envelope-delivery instructions to Alphys, he hurried back, eager to tell Gaster.

* * *

 

"And you're sure that's safe?!" the doctor demanded.

"Well, the guy who gave me the idea seemed pretty sure, but he was technically me from twenty minutes ago," said Sans, shrugging, "He asked me to give you a kiss, by the way."

"J-just a moment, I need to sit down," said Gaster.

"Hey, you okay?"

Gaster nodded and walked quickly toward his office, beckoning Sans to follow.

They both sat down, Gaster at his desk, and Sans on the cot behind him.

"I'm sorry, that just sounds a bit more _complicated_ than I was expecting. I have to travel back several weeks to deliver an important message, and I'm not sure what will happen if I make a mistake."

"Oh," said Sans, and then, "Hey, you'll be fine!" He stood up and moved closer to Gaster. Placing his hand between the doctor's shoulder blades, he rubbed small, comforting circles into the fabric between them. "You're just completing a loop," he told him, "closing a circuit. You're not gonna mess up. I'd remember if you messed up."

Gaster turned to give him a skeptical look.

"I was kidding, sorry."

"It's a real concern, Sans. What if I change something and none of this ever happens as a result?"

"Then you wouldn't have been able to go back and mess it up in the first place."

"I'm not just talking about time travel, here. I mean all of it." He frowned. "The two of us," he added in a whisper.

"Oh." The thought was painful; Sans pushed it aside. "Don't think of it as something that can be changed, then. Think of it like a fixed track. You're just going back in time to tell yourself to go back in time. Then you come back here, and don't have to deal with it again."

Gaster scoffed. "If it's a fixed track, then all of this jumping around is but a useless distraction, and we have no reason to keep pursuing it. If we can't go back and change things then what's the point?"

Sans moved to Gaster's left, leaning his weight on the desk next to him. "What'd you wanna change in the first place?" he asked.

"It's... silly."

"What? Going back and preventing the barrier?"

"No, not that. The barrier is a terrible prison, but it's the only thing that prevented humans from just wiping us all out after the war. No, I... I wanted to go back to the beginning of things in the underground. Get the core set up immediately, and let our civilization build up around its infrastructure, instead of having to redo the entire grid. I'd keep watch over prince Asriel, and the human Princelet if they showed up. I thought, if I could just prevent that whole tragedy from happening, maybe things would have been different. Asgore, not knowing such terrible loss, would have no reason to declare war on intruding humans. His wife would not leave him, and they would both grow old and die happy, while their son took over."

"You'd let Asgore die?"

"Don't say it like that! He wasn't ever meant to rule for such a great length of time. He may not age like the rest of us, but the years have taken their toll on him in other ways. And if I went back and got the cannon working, and broke the barrier down sooner, I thought maybe monster kind wouldn't have had to spend hundreds of years trapped here, miserable."

"Well, it doesn't sound all that silly to me, Doc. Sounds like a pretty noble dream."

Gaster looked away. "But now that I'm close, now that I have the means to go back and make it a reality? I don't really _want_ to. Because I'm selfish, and I like the way my life is going at the moment." He shot Sans a meaningful look. "I don't want to give up everything and be suddenly without you. Though, I'm sacrificing Asgore's _well-being_ for that."

Sans laughed. "Is that really what's got you torn about it? Gaster, Doc, you know there's an easy solution to that, right?"

"What?"

"If it was something you were set on doing, I could go back with you and help make sure it pans out."

"I can't ask that of you, Sans."

"You don't have to, I'm making the offer. Gaster? I'd go anywhere with you. I'd follow you into the void, across time, throughout this whole damn cavern. For any reason. If you wanted me to, I'd be there with you." He felt a tightening in his chest. "Gaster, I-" There was no sense waiting for a perfect, romantic moment to tell him the truth. The moment they were in right then called for honesty.

He brought both hands up in front of his chest, making sure Gaster saw them.

' _I love you_ ,' he signed, and his voice echoed the words.

"I love you."

Gaster stared back at him, his cheeks darkened with color. "I-I love you too. Come here."

Before he could do anything else, Gaster had wrapped both arms around him, pulling him into an a tight embrace. There was no more oxygen in the room, helium had taken its place and if Sans hadn't been held down at that moment, if they weren't trapped deep within a mountain, he would have floated off into space.

"I love you so much, Sans."

Sans wasn't sure whether he had hoped or had feared that things would be different between them after that, but things stayed as they were. The connection they shared had already been there, waiting.

* * *

 

Over the next several days, the two of them worked on a strategy to get Gaster back in time, and how he would return. They watched the security footage of that morning, they took practice trips together, leaping back and forth a week's worth of time. Sans would take any measure to have Gaster feeling secure and prepared to handle this. It was destiny, he reasoned.

Finally, the day arrived. "I'm ready," Gaster told him. He showed up to work in the same clothes he had worn in the footage, and honestly looked like he hadn't slept at all.

They had an agreement that Gaster would make the trip after work, and that Sans would round up the white dog and keep it out of the way until Gaster came back.

Once it was just the three of them, he opened a door to the void, in the same room where they were keeping the (now dissembled) cannon. "Alright, I should be back within ten minutes," he told Sans. "Wish me luck."

"Good luck. I love you." He let Gaster lean down to kiss him, and he held tightly to the squirming dog in his arms. "Be safe," he whispered, as Gaster pulled away.

"Of course. I love you too, and I'll see you soon."

He slipped into the void, and Sans let out the breath he had been holding. The dog barked, trying to wiggle free from his grip.

"Not yet, buddy, you're staying with me until he gets back. Can't have you getting involved in this one."

The dog whimpered, and Sans sat down in a nearby chair as the seconds ticked by.

The seconds turned to minutes, and the minutes to a full hour. The dog had long since fallen asleep at his feet, and he had spent the last half an hour pulling loose threads from the cuff of his lab coat sleeve and wrapping them around his fingers. He wasn't sure what to do. He had no way to contact the doctor if he got lost, or if something had happened along the way and things didn't go according to plan.

He slumped into the chair, he felt helpless. _Things WILL go according to plan_ , he told himself.

Footsteps echoed down the hall beside him, coming his way.

"Sans?" Gaster called out.

He flew from his seat and ran to the hallway, nearly colliding with Gaster as he turned the corner.

"Oh! Sans? Are you alright?"

Sans wrapped his arms tightly around Gaster's waist. "You were gone way longer than ten minutes!" he wheezed.

"Oh goodness! My aim must have been off on my way back, I'm sorry if I worried you." He placed his hands gently onto Sans's shoulders. "You're alright, though?"

"Of course. Are you?"

Gaster smiled. "I'm fine. Thank you. The trip went smoothly, and everything should happen as it previously played out."

Sans nestled his face into the side of Gaster's lab coat. "Good," he muttered, "I'm glad."

All the commotion of Gaster's return had awoken the little dog, who squeezed himself between their feet, demanding some of the attention being passed around for himself. Sans reluctantly pulled away from Gaster for a moment to reach down and scratch the little pest between his ears.

"Thanks for behaving this time, buddy," he said.

The dog yipped and sped off, disappearing down the hall. No doubt he was going to eat more of their equipment.

"Alright, I have had my fair share of excitement," said Gaster. "Let's go home for the night."

Sans smirked. "You mean your place?"

"Y-yes, that's what I meant."

"You look so cute when you fumble like that."

"Hush."

Gaster opened up the void, and Sans reached out for his hand as they stepped in together.

The world around them was changing, the nature of their work, changing. They too, eventually would change. But each had the other in his life, and they would face whatever happened together.

 

**Notes for the Chapter:**

> Again, Thank you.

**Author's Note:**

> Critiques are more than welcome, I'm still finding my footing in the realm of writing, and am looking to improve as I go.


End file.
